JPH083856A - Laminated nonwoven structure - Google Patents

Abstract

PURPOSE:To obtain a laminated nonwoven structure having a high tensile strength and peel strength and excellent dimensional stability, flexibility, water absorption properties and wear resistance by laminating filament nonwoven fabric of thermoplastic aliphatic polyamide base to natural fiber nonwoven fabric and integrating. CONSTITUTION:Filament nonwoven fabric of thermoplastic aliphatic polyamide- base polymer such as nylon 6 having >=dl and <=8dLl single yarn fineness is laminated to nonwoven fabric obtained by interlacing natural fiber web such as cotton. Then the laminate is fused and integrated treated by an ultrasonic fusing device equipped with a pattern roll in such a way that the cotton fibers positioned at least in a boundary zone of both the nonwoven fabric layers in a region in which the nylon 6 filament and the cotton fibers are fused in a dotted state are embedded and fixed in the molten part of the nylon 6 satisfying both equations of 2<=A<=40 and 7<=B<=80 in which A is the ratio (%) of the area of the total fused region to the whole surface area of a nonwoven structure and B is the density (dots/cm<2>) of the fused region in a dotted state to form the laminated nonwoven structure.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminated non-woven structure in which a long-fiber non-woven fabric layer made of a thermoplastic aliphatic polyamide polymer and a natural-fiber non-woven fabric layer are laminated. Laminated non-woven fabric, which has high dimensional stability and flexibility, has dyeability and water absorbency, and has high abrasion resistance, which is suitable as a material for medical / sanitary materials, clothing, and daily life-related materials. It concerns structures.

[0002]

2. Description of the Related Art Conventionally, a laminated non-woven structure is known in which a thermoplastic synthetic fiber nonwoven fabric layer and a natural fiber nonwoven fabric layer are laminated. For example, in Japanese Examined Patent Publication No. 54-24506, a breathable heat-welding layer made of a thermoplastic synthetic fiber nonwoven fabric and a breathable non-heat-welding layer made of natural fibers are laminated.
The heat-welding substance is scatteredly arranged on the non-heat-welding layer, and the fusion zone of the heat-welding substance and the heat-welding layer penetrates from both sides of the non-heat-welding layer to bond and sandwich the non-heat-welding layer. Laminated nonwoven structures having this structure have been proposed. However, this laminated non-woven structure has excellent water absorbency due to the laminated natural fibers, and because the heat-welding layer penetrates into the non-heat-welding layer, that is, the natural fiber layer by the heat-welding treatment, it has good tensile strength and peeling. Although it has excellent mechanical properties such as strength, it has a problem that the texture such as flexibility deteriorates. In addition, this laminated non-woven structure has a step of laminating a breathable heat-welding layer and a breathable non-heat-welding layer, and a heat-sealing sheet layer for impregnation on the non-heat-welding layer. , A step of infiltrating the fused portion of the heat-welding substance and the heat-welding layer from both sides of the non-heat-welding layer by ultrasonic welding to develop a structure in which the non-heat-welding layer is adhesively sandwiched, From the viewpoint of manufacturing technology, such as requiring a step of peeling the weldable sheet leaving the melted portion, it is complicated and economically inferior.

[0003]

DISCLOSURE OF THE INVENTION The present invention is a laminated non-woven structure comprising a long-fiber non-woven fabric layer made of a thermoplastic aliphatic polyamide polymer and a natural-fiber non-woven fabric layer, and having a high tensile strength. High peel strength, dimensional stability and flexibility, dyeability and water absorbency, and high abrasion resistance, suitable for medical / sanitary materials, clothing, and daily life related materials. It is intended to provide a non-woven structure.

[0004]

The inventors of the present invention have arrived at the present invention as a result of extensive studies to achieve the above object. That is, the present invention has the following configurations as its gist. 1) A non-woven fabric layer composed of long fibers made of a thermoplastic aliphatic polyamide polymer and a non-woven fabric layer formed by mechanically entangled natural fibers are laminated, and the long fibers and the natural fibers are fused. In the laminated non-woven structure having a point-like fused area, the natural fibers located in at least the boundary surface of the two non-woven fabric layers in the point-like fused area are all points for the total surface area of the non-woven structure. Ratio A of the fused area
(%) And dot-like fused area density B (dots / cm ² ) satisfy the following formulas (1) and (2), respectively, and are fixed in a state of being embedded in the melted portion of the long fiber as a whole. A laminated non-woven structure characterized by being integrated. 2 ≦ A (%) ≦ 40 (1) 7 ≦ B (points / cm ² ) ≦ 80 ··············· (2) 2) The laminated non-woven structure, wherein the single fiber fineness of the long fibers made of the thermoplastic aliphatic polyamide polymer is 1 denier or more and 8 denier or less. .

Next, the present invention will be described in detail. First, regarding the non-woven fabric layer composed of long fibers in the present invention, this non-woven fabric layer is composed of a thermoplastic aliphatic polyamide polymer having fiber forming property. Examples of the polyamide polymer include polyimino-1-oxotetramethylene (nylon 4), polytetramethylene adipamide (nylon 46), polycapramide (nylon 6), polyhexamethylene adipamide (nylon 6).
6), polyundecanamid (nylon 11), polylaurolactamide (nylon 12), polymetaxylene adipamide, polyparaxylylene decanamide, polybiscyclohexylmethane decanamide or a monomer thereof as a structural unit. A polyamide-based copolymer that can be used. In particular,
In the case of polytetramethylene adipamide, polytetramethylene obtained by copolymerizing polytetramethylene adipamide with other polyamide components such as polycapramide, polyhexamethylene adipamide, and polyundecamethylene terephthalamide in an amount of 30 mol% or less. It may be an adipamide-based copolymer.
When the copolymerization rate of the other polyamide component exceeds 30 mol%, the melting point of the copolymer is lowered, and the laminated non-woven structure obtained by using the non-woven fabric made of fibers of these copolymers is used under high temperature conditions. If so, mechanical properties and dimensional stability will be reduced, which is not preferable. In the present invention, various additives such as a matting agent, a pigment, a deodorant, a light stabilizer, a heat stabilizer, and an antioxidant may be added to the thermoplastic polymer having the fiber-forming property, if necessary. The agent can be added within a range that does not impair the effects of the present invention.

The long fiber non-woven fabric layer in the present invention is a spunbonded non-woven fabric composed of the above long fibers. The long fibers are composed of a blend of the above-mentioned polymers alone and a blend of two or more different polymers selected from the above-mentioned polymers within the range not impairing the melt spinnability. May be Further, the form of the long fibers may be one in which two or more different polymers selected from the above polymers are arranged in a core-sheath type or a parallel type.

The spunbonded nonwoven fabric is selected from the above-mentioned polymers alone, or a blend of two or more different polymers selected from the above-mentioned polymers, or selected from the above-mentioned polymers. The two or more different polymers are melt-spun by the so-called spunbond method so that they are arranged in a core-sheath type or a parallel type. After the fiber is pulled / thinned at a take-up speed of 3000 to 6000 m / min, it is opened with a fiber-opening device and collected / deposited on the moving collection surface to form a fiber composed of the long fibers. It can be obtained by obtaining a woven web and subjecting the obtained nonwoven web to a partial hot press treatment. When melt-spun by the spunbond method, the take-up speed is 3
000 to 6000 m / min is preferable. If the take-up speed is less than 3000 m / min, the mechanical properties and dimensional stability of the obtained web will not be improved because the molecular orientation degree of the spun filament will not be sufficiently increased, while the take-up speed will be 6000 m / min.
If the amount exceeds the limit, the spinnability at the time of melt spinning decreases, which is not preferable. When the non-woven web is subjected to the partial hot-pressing treatment, it is preferable to use a roll which is heated and has a projection-shaped engraved pattern on its surface, that is, an embossing roll and a metal roll which is heated and has a smooth surface. By passing the non-woven web between these rolls, the web constituent fibers in the portion corresponding to the engraved pattern portion can be partially thermocompressed.

The long fiber nonwoven fabric layer in the present invention is composed of the above long fibers, and it is preferable that the single fiber fineness of the long fibers is 1 to 8 denier. When the monofilament fineness is less than 1 denier, mechanical properties such as tensile strength of a laminated non-woven structure obtained by laminating a long fiber non-woven fabric layer and a natural fiber non-woven fabric layer are not improved, and long fibers are obtained. At that time, the spinnability during melt spinning is deteriorated, while when the single fiber fineness exceeds 8 denier, the texture of the resulting non-woven fabric becomes hard and a flexible non-woven structure cannot be obtained. Not preferable. Therefore, in the present invention,
The single fiber fineness of the long fibers is 1 to 8 denier, preferably 2 to 5 denier.

The long fiber nonwoven fabric layer in the present invention preferably has a basis weight of 10 to 70 g / m ² .
When the basis weight is less than 10 g / m ² , the adhesive strength of the laminated nonwoven structure obtained by laminating and integrating the composite long fiber nonwoven fabric layer and the natural fiber nonwoven fabric layer becomes low, while the basis weight is 70
When it exceeds g / m ² , it becomes difficult to apply the obtained laminated non-woven structure to a field requiring flexibility, or when the laminated non-woven structure is used as a material for clothes. The long fiber non-woven fabric layer, which is harder than the natural fiber non-woven fabric, irritates the skin, or the natural fiber non-woven fabric is laminated on this non-woven fabric and then subjected to a fusion treatment using an ultrasonic fusing device to integrate the fibers, thereby reducing the processing speed. However, it is necessary to supply a large amount of ultrasonic energy, which is not preferable. Therefore, in the present invention, the basis weight of the long fiber nonwoven fabric layer is set to 10 to 70 g / m ^2, and preferably 15 to 50 g / m ² .

Next, regarding the non-woven fabric layer according to the present invention in which the natural fibers are mechanically entangled with each other, the natural fibers constituting the non-woven fabric layer include cellulosic fibers such as cotton fibers and hemp fibers. It also includes animal fibers such as ramie, silk staple fibers, natural pulp, and various recycled staple fibers represented by rayon. In the present invention, as a starting material for this non-woven fabric layer, combed yarn that has not been subjected to bleaching processing,
Bleached cotton that has been bleached or various fluff obtained from woven or knitted fabric can also be used. When using fluff as the starting material, the fluff machine that can be effectively used includes a ratchet machine, a notch breaker, a garnet machine, and a cutting machine. The type and combination of anti-fluffing machines used depend on the shape of the woven or knitted fabric to be fluffed and the thickness or twisting strength of the constituent threads, but multiple identical anti-fluffing machines are connected in series. It is more effective to use two or more types of anti-hairbrushing machine in combination. The defibration rate (%) by the fluffing machine is preferably in the range of 30 to 95%. When the defibration rate is less than 30%, unwoven fibers are present in the card web, so that not only the surface of the non-woven fabric is rough but also natural fibers are three-dimensionally mechanically processed by the high pressure liquid columnar flow treatment. When the entanglement is performed, the high-pressure liquid columnar flow does not sufficiently penetrate the undisentangled fiber portion, while the disentanglement rate is 95
If it exceeds%, the laminated non-woven structure obtained by laminating and integrating the composite long-fiber non-woven fabric cannot obtain sufficient surface friction strength, which is not preferable. The defibration rate (%) here is obtained by the following formula (3). Disentanglement rate (%) = (weight of woven fabric-weight of filamentous material) x 100 / weight of woven fabric ... (3)

The natural fiber non-woven fabric layer in the present invention is made of the above-mentioned natural fibers, and the fibers are mechanically entangled with each other. That is, the natural fibers are mechanically entangled by the high-pressure liquid columnar flow treatment or the needle punching treatment. Especially in the former case, the fibers are entangled three-dimensionally and the bulkiness of the non-woven fabric is improved and the flexibility is high. Since the property is also improved, for example, a laminated non-woven structure obtained by laminating and integrating with the long fiber non-woven fabric is preferable as a material for sanitary materials or life-related materials. This non-woven fabric layer is made of a single material or a mixture of a plurality of materials selected from the above natural fiber materials as a starting material. It can be easily obtained by subjecting the obtained web to mechanical entanglement between fibers by high pressure liquid columnar flow treatment or needle punching treatment. The card web can be variously selected according to the degree of arrangement of the constituent fibers. For example, a parallel web arranged in the traveling direction of the card machine, a web in which parallel webs are crosslaid, a random web arranged in random, or a medium degree of both. Examples thereof include a semi-random web and the like.
Further, when it is desired to develop it as a material for clothing, it is preferable to use a card web in which the aspect ratio of the strength of the nonwoven fabric is about 1/1.

In the case of the high-pressure liquid columnar flow treatment, for example, a large number of injection holes having a hole diameter of 0.05 to 1.5 mm, particularly 0.1 to 0.4 mm are arranged in one row or a plurality of rows with a hole interval of 0.05 to 5 mm. The injection pressure is 5 to 150 kg / c
A method of injecting a high-pressure liquid of m ² G from the injection hole and colliding with a card web placed on the porous support member to give a three-dimensional entanglement between the fibers is adopted. The ejection holes are arranged in rows in a direction orthogonal to the traveling direction of the card web. As the high-pressure liquid, room temperature water or warm water can be used. The distance between the injection hole and the web is preferably 1 to 15 cm. This distance is 1
If the distance is less than 15 cm, the texture of the composite non-woven fabric obtained by this treatment is disturbed. On the other hand, if the distance exceeds 15 cm, the impact force when the liquid flow collides with the laminate is reduced and the three-dimensional entanglement becomes sufficient. Not applied and neither is preferred. This high pressure liquid columnar flow treatment may be performed in at least two stages. That is, in the first-stage treatment, a high-pressure liquid flow having a pressure of 5 to 40 kg / cm ² G is jetted to collide with the web to preliminarily entangle the constituent fibers of the web. In this first-stage treatment, if the pressure of the liquid flow is less than 5 kg / cm ² G, the constituent fibers of the web cannot be pre-entangled with each other, while the pressure of the liquid flow is 40 kg / cm ² G Above the range, when the high-pressure liquid flow is jetted into the web and collided, the constituent fibers of the web are disturbed by the action of the liquid flow, and the web is disturbed in texture and is unfavorable. Subsequently, in the second step, a high-pressure liquid flow having a pressure of 50 to 150 kg / cm ² G is jetted to collide with the web, and the fibers constituting the web are three-dimensionally entangled with each other so as to be densely integrated as a whole. . In this second stage treatment, the liquid stream pressure is 5
If it is less than 0 kg / cm ² G, the three-dimensional entanglement between fibers as described above cannot be sufficiently formed, while
When the pressure of the liquid flow exceeds 150 kg / cm ² G, the bulkiness and flexibility of the resulting nonwoven fabric are not improved, which is not preferable either. Depending on the basis weight of the web, as a third stage process following the second stage process, the second side process is performed again from the side opposite to the second stage process side under the same conditions as the second stage process. It is possible to obtain a non-woven fabric in which fibers are closely entangled with each other on the front and back. Examples of the porous support member for carrying the web used for performing the high-pressure liquid columnar flow treatment include, for example, a mesh screen or a perforated plate made of wire mesh or synthetic resin of 20 to 100 mesh.
The high-pressure liquid flow is not particularly limited as long as it can penetrate the web. The mesh structure of the porous support member is 20
The number of fibers / 25 mm to 200/25 mm is preferable, and when it is less than 20/25 mm, when the high-pressure liquid columnar flow collides with the web, the fibers pass through the mesh screen together with the columnar flow, and Dropout occurred, while 20
If the number exceeds 0/25 mm, the amount of energy required for the high-pressure liquid columnar flow to pass through the web and the mesh screen increases, resulting in an increase in production cost. After performing the high pressure liquid flow treatment, excess moisture is removed from the treated web. A known method can be adopted for removing the excess water. For example, a nonwoven fabric can be obtained by mechanically removing excess moisture to some extent using a squeezing device such as a mangle roll, and then using a drying device such as a hot band circulation dryer of the saxion band system to remove residual moisture. it can.

The natural fiber nonwoven fabric layer in the present invention preferably has a basis weight of 30 to 200 g / m ² . When the basis weight is less than 30 g / m ² , the abundance of natural fiber per unit area is too small to sufficiently provide the water absorption targeted by the present invention, while the basis weight is 200 g / m ^2.
If it exceeds m ² , the peel strength of the laminated non-woven structure obtained by laminating with the long-fiber non-woven fabric and forming point-like fused areas by using an ultrasonic fusing device is sufficient. It does not improve and neither is preferable. Therefore, in the present invention, the basis weight of this natural fiber nonwoven fabric is 30 to
200 g / m ² , preferably 50-150 g / m ²
And

Next, the laminated nonwoven structure of the present invention will be described. The laminated non-woven structure of the present invention has a point-like fused area formed by laminating the long-fiber non-woven fabric layer and the natural-fiber non-woven fabric layer and fusing the long-fiber and the natural fiber, and The natural fibers located at least at the boundary surface of the two nonwoven fabric layers in the melt-bonded area are fixed in a state of being embedded in the melted portion of the long fibers so that they are integrated as a whole. This point-like fused area has a frequency of about 2
The convex protrusion is formed by using an ultrasonic fusing device including an ultrasonic oscillator, which is generally called a 0 KHz horn, and a pattern roll having a convex protrusion in a dot shape or a strip shape on the circumference. The fibers that come into contact with the portions corresponding to are fused together. The spot-shaped fused areas have a specific area and a specific arrangement with respect to the total surface area of the non-woven structure, and the individual dotted-shaped fused areas do not necessarily have a circular shape.
Besides circular shape, for example, cross shape, − shape, diamond shape, T shape, □ shape,
Although it may have any shape such as a triangle shape, the ratio A (%) of the area of all the spot-shaped fused areas to the total surface area of the non-woven structure and the point-shaped fused area density B (points / cm ² ) are respectively It is necessary to satisfy the expressions (1) and (2). The ratio A of the area of all point-like fused areas to the total surface area of the nonwoven structure A
When the (%) is less than 2%, a laminated non-woven structure obtained by integrating the long fiber non-woven fabric and the natural fiber non-woven fabric by forming point-shaped fusion zones by using an ultrasonic fusion device The peel strength of the body does not improve sufficiently, while
If the area ratio A (%) exceeds 40%, the flexibility and bulkiness of the obtained laminated nonwoven structure will decrease. Therefore, in the present invention, the area ratio A (%) is 2 to 40%. , Preferably 4 to 25%. Further, if the density of spot-shaped fused areas B (points / cm ² ) is less than 7 points / cm ² , not only the adhesive strength of the obtained laminated non-woven structure, that is, the peel strength is lowered, but also strong spots are formed. On the other hand, the same area density is 80 points / cm
^When it exceeds ² , the flexibility and bulkiness of the obtained laminated non-woven structure deteriorates. Therefore, in the present invention, the area density B
(Point / cm ² ) is 7 to 80 points / cm ² , preferably 8 to
50 points / cm ² .

The ultrasonic fusing apparatus which can be used in the present invention comprises a known apparatus, namely an ultrasonic oscillator generally called a horn having a frequency of about 20 KHz, and a point-like or band-like convex projection on the circumference. And a pattern roll to be used. The pattern roll is disposed below the ultrasonic oscillator, and the object to be processed is passed between the ultrasonic oscillator and the pattern roll. The convex protrusions arranged on the pattern roll may be arranged in one row or a plurality of rows, and when the arrangement is a plurality of rows, they may be arranged in parallel or in a staggered arrangement. During the fusion treatment, air pressure is applied to the horn to apply pressure. The linear pressure between the horn and the pattern roll is usually 1 to 10 kg / cm, and the linear pressure is 1 k.
When it is less than g / cm, the pressing force against the laminate of the composite long-fiber non-woven fabric layer and the natural fiber non-woven fabric layer is insufficient and fusion does not occur. On the other hand, when the linear pressure exceeds 10 kg / cm,
The laminated non-woven structure obtained when the pressing force against the spot-shaped fused area is too high and the composite long-fiber nonwoven fabric layer corresponding to the fused area is thermally decomposed or, in extreme cases, perforated. Adhesive strength is reduced and neither is preferable. The laminated non-woven structure of the present invention is obtained by subjecting a laminate of the long fiber non-woven fabric and the natural fiber non-woven fabric to a fusion treatment by using the ultrasonic fusion device described above, thereby forming the two Natural fibers located at least at the boundary surface of the non-woven fabric layer are fixed in a state of being embedded in the fused portion of the long fibers and integrated as a whole. FIG. 1 is a schematic view showing a cross section of the spot-shaped fused area in the laminated nonwoven structure of the present invention. In the figure, 1 is a long fiber layer melted in a point fusion area, 2 is a natural fiber, and as is clear from the figure, the natural fiber 2 located at least at the boundary surface of both nonwoven layers in the point fusion area is , Melting part where long fibers are melted, ie 1
The two non-woven fabric layers have such an adhesive structure in the point-like fused area,
The laminated non-woven structure has high peel strength.

[0016]

The laminated non-woven structure of the present invention is excellent in dimensional stability, has dyeability, and is durable because it is composed of a non-woven fabric layer consisting of long fibers of a thermoplastic aliphatic polyamide polymer on one side. It has excellent abrasion resistance and has dyeability and water absorbency because it is composed of a non-woven fabric layer on the other side in which natural fibers are mechanically entangled with each other. Moreover, since natural fibers are entangled three-dimensionally, excellent flexibility is provided. Furthermore, the natural fibers located at least at the boundary surface between the two nonwoven fabric layers in the spot-shaped fusion area formed by fusing the long fibers and the natural fibers are fixed in a state of being embedded in the fusion portion of the long fibers. Since it has an adhesive structure, it is a laminated non-woven structure with high peel strength.

[0017]

EXAMPLES Next, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. In the examples, each characteristic value was measured by the following method. Melting point (℃): Differential scanning calorimeter DS manufactured by Perkin Elma
Using C-2 type, sample weight 5 mg, temperature rising rate 20 ℃
The temperature that gives the maximum extremum of the melting endothermic curve obtained by measuring as / min was defined as the melting point (° C). Relative viscosity: Sulfuric acid having a concentration of 96% by weight was used as a solvent, and the concentration was measured by a conventional method under the conditions of a sample concentration of 1.0 g / 100 cc and a temperature of 25 ° C. Unit weight (g / m ² ): 10 cm in length from standard state sample
After making 10 pieces of 10 cm wide sample piece to reach the equilibrium water content, weigh each sample piece (g) and calculate the average value of the obtained values per unit area (m ² ). Unit weight (g /
m ² ). Tensile strength (kg / 5cm width) and tensile elongation (%):
It was measured according to the method described in JIS-L-1096A. That is, a total of 10 sample pieces having a sample length of 10 cm and a sample width of 5 cm were prepared, and a constant speed extension type tensile tester (Tensilon UTM-made by Toyo Baldwin Co., Ltd. 4-1-100) was used for elongation at a tensile speed of 10 cm / min, and the average value of the load values during cutting (kg / 5 cm width) obtained was measured for tensile strength (kg / cm).
5 cm width), and the average value of the elongation rate (%) at break was taken as the tensile elongation (%). Delamination strength (g / 5 cm width): A total of 10 sample pieces with a sample length of 10 cm and a sample width of 5 cm were prepared, and a constant speed extension type tensile tester (Toyo Bold Win Tensilon UTM-4-1-10
0) and a tensile speed of 10 cm / min to form a natural fiber non-woven fabric layer from the long fiber non-woven fabric layer from the end of the laminated structure to 5c.
The load value (g /
The average value of (5 cm width) was defined as the delamination strength (g / 5 cm width). Area shrinkage (%): A total of 5 sample pieces each having a sample length and a sample width of 25 cm were prepared, and boiling water was applied to each sample piece for 3 minutes by using boiling water. At this time, the area S1 (cm ² ) of the sample piece before the boiling water treatment and the area S of the sample piece after the boiling water treatment
2 (cm ² ) was determined, and the average value of the values calculated from the obtained S1 and S2 by the following formula (4) was defined as the area shrinkage rate (%). Area shrinkage (%) = [1- (S2 / S1)] × 100 (4) Stiffness (g): sample length 10 cm, sample width 5 cm Total 5 A point was created, and each sample piece was bent in the lateral direction to form a cylindrical object, and the ends were joined together to form the bending resistance measurement sample. Then, for each measurement sample, the maximum obtained was obtained by compressing in the axial direction using a constant-speed extension type tensile tester (Tensilon UTM-4-1-100 manufactured by Toyo Baldwin Co., Ltd.) at a compression rate of 5 cm / min. The average value of the load values (g) was defined as the bending resistance (g). Therefore, a lower value of this bending resistance means a softer nonwoven fabric. Water absorption (mm): Measured according to the Bayrek method described in JIS-L-1096. Abrasion resistance: The abrasion resistance was evaluated according to the 45R method using the Gakushin type friction resistance tester described in JIS-L-1084 A-1. That is, 14 cm x 5 in the warp direction x the transverse direction of the non-woven structure.
cm and 5 cm x 14 cm sample pieces were made at 5 points each,
For each sample piece, the long fiber non-woven fabric layer was placed outside and attached to the tester, while a 45R friction element was specified as JIS-L-
Using the white cloth cotton cloth No. 3 for dyeing fastness described in 0803, after rubbing 100 times under the condition of an applied load of 200 g and a reciprocating reciprocating speed of 30 times / minute, the appearance of the sample piece is visually observed. Then, the evaluation was made in the following 5 grades. Grade 5: No change on friction surface, Grade 4: Fiber on friction surface is slightly disturbed, Grade 3: Fiber on friction surface is slightly disturbed, but there is no practical problem, Grade 2: Friction surface The fibers of (1) have a slightly pill-like form, and the fibers of the first grade: friction surface have a pill-like form.

Example 1 First, a spunbonded nonwoven fabric made of nylon 6 long fibers was prepared using a polycapramide (nylon 6) chip having a melting point of 225 ° C. and a relative viscosity of 2.53. That is, the polymer chip was melted by using an extruder type melt extruder, and this was passed through a spinneret having 180 spinning holes of 0.4 mm in diameter at a spinning temperature of 260 ° C. and a single hole discharge rate of 1.5 g / min. After melt spinning and cooling the spun yarn, after pulling and thinning with a take-up speed of 4500 m / min using an air sawer arranged below the spinneret,
The web is opened using a fiber opener, collected and deposited on a moving collection surface to form a web, and the obtained web has a tip area of 0.
A heat-embossing roller having a 6 mm ² protrusion-shaped engraved pattern portion arranged at a pressing area ratio of 13.2% and a density of 20 points / cm ² and a metal roller having a smooth surface were used, and the treatment temperature was 190 ° C.
Moreover, a partial pressure-bonding treatment was performed at a processing speed of 10 m / min with a linear pressure of 50 kg / cm to obtain a nylon 6 long fiber spunbonded nonwoven fabric having a single fiber fineness of 3.0 denier and a basis weight of 30 g / m ² . Separately, a non-woven fabric having an average single fiber fineness of 1.5 denier and an average fiber length of 25 mm bleached from cotton was used to fabricate three-dimensionally entangled cotton fibers. That is, using the bleached cotton as a starting material, the fiber arrangement is random and the basis weight is 35 g by a random card machine.
/ M ² random card web was prepared, and then the obtained web was placed on a wire mesh of 70 mesh moving at a moving speed of 20 m / min and subjected to high-pressure liquid flow treatment. In the high-pressure liquid flow treatment, injection holes with a hole diameter of 0.1 mm have a hole spacing of 0.6.
Using a high-pressure columnar water stream treatment device arranged in a line in mm,
A columnar water stream was applied in two steps from a position 50 mm above the web. In the first stage treatment, the pressure is 30 kg /
cm ² G, and the pressure was 70 kg / c in the second stage treatment.
m ² G. The second stage treatment was performed twice from the front and back of the web. Then, after removing excess water from the treated product using a mangle roll, the treated product was dried using a hot air dryer at a temperature of 100 ° C., and the cotton fibers were densely three-dimensionally entangled. A non-woven fabric having a basis weight of 35 g / m ² was obtained. Next, the nylon 6 long-fiber spunbonded non-woven fabric and the cotton fiber non-woven fabric obtained above were laminated, and an ultrasonic wave oscillator with a frequency of 19.15 KHz and a point-shaped convex projection on the circumference were used as an area ratio (roll total Ratio of area of all convex protrusions to surface area) 11% and density 18
Using an ultrasonic fusing device consisting of a pattern roll arranged at points / cm ² , ultrasonic fusing treatment was applied at a processing speed of 30 m / min and a linear pressure of 1.5 kg / cm to obtain a laminated nonwoven fabric. The structure was obtained. Then, acid dye Kayanol G
The laminated non-woven structure obtained above was dyed with a jet dyeing machine using a 1% by weight solution of rey P (manufactured by Nippon Kayaku Co., Ltd.) Could be dyed. The properties of the resulting laminated nonwoven structure are shown in Table 1.

Examples 2 to 5 The single fiber fineness of the long fibers constituting the spunbonded nonwoven fabric is 0.8 denier (Example 2), 1.0 denier (Example 3), 8.0 denier (Example 4). And a laminated non-woven structure were obtained in the same manner as in Example 1 except that the denier was 10.0 (Example 5). The properties of the resulting laminated nonwoven structure are shown in Table 1.

Example 6 A laminated nonwoven structure was obtained in the same manner as in Example 1 except that the basis weight of the long fiber spunbonded nonwoven fabric was 70 g / m ² . The properties of the resulting laminated nonwoven structure are shown in Table 1.

Examples 7 to 10 The area ratio of the convex protrusions of the pattern roll in the ultrasonic fusing device was 5% (Example 7), 16% (Example 8) and 20%.
A laminated nonwoven structure was obtained in the same manner as in Example 1 except that (Example 9) and 40% (Example 10) were used. The properties of the resulting laminated nonwoven structure are shown in Table 2.

Examples 11 to 13 The distribution density of the convex projections of the pattern roll in the ultrasonic fusing apparatus was 9 points / cm ² (Example 11), 36 points / cm ²
A laminated nonwoven structure was obtained in the same manner as in Example 1 except that (Example 12) and 80 points / cm ² (Example 13) were used. The properties of the resulting laminated nonwoven structure are shown in Table 2.

Comparative Example 1 A hot embossing roll having a pressing area ratio of 12% and a hot metal roll having a smooth surface were used in place of the ultrasonic fusing device, the treatment temperature was 200 ° C., the linear pressure was 100 kg / cm, and the working was performed. A laminated non-woven structure was obtained in the same manner as in Example 1 except that the partial hot press treatment was performed at a speed of 10 m / min. The properties of the resulting laminated nonwoven structure are shown in Table 1.

Comparative Examples 2 and 3 In the same manner as in Example 1 except that the area ratio of the convex projections of the pattern roll in the ultrasonic fusing device was set to 1% (Comparative Example 2) and 45% (Comparative Example 3). , A laminated non-woven structure was obtained.
The properties of the resulting laminated nonwoven structure are shown in Table 2.

Comparative Examples 4 and 5 The density of the convex projections on the pattern roll in the ultrasonic fusing apparatus was 4 points / cm ² (Comparative Example 4) and 90 points / cm ^2.
A laminated nonwoven structure was obtained in the same manner as in Example 1 except that (Comparative Example 5) was used. The properties of the resulting laminated nonwoven structure are shown in Table 2.

[0026]

[Table 1]

[0027]

[Table 2]

The laminated non-woven structures obtained in Examples 1, 3, 4, 6, 8, 9, and 12 had high tensile strength and peeling strength as shown in Table 1, and excellent dimensional stability. It had water absorbency and high wear resistance. The laminated nonwoven structure obtained in Example 3 was also excellent in flexibility because the denier of the long fibers was low. The laminated non-woven structure obtained in Example 2 was excellent in flexibility because the long fiber denier was lower, but was slightly inferior in abrasion resistance. The laminated non-woven structures obtained in Examples 4 and 5 were excellent in tensile strength and peel strength because the long fibers had a high denier, but were slightly inferior in flexibility to Example 1. That is, in the laminated nonwoven structure of the present invention, it is understood that the flexibility increases as the denier of the long fibers decreases, while the peel strength and the flexibility decrease when the denier increases. In the laminated nonwoven structure obtained in Example 7, the area ratio of the convex projections of the pattern roll in the ultrasonic fusing device was 5%, and all the point-like fused areas to the entire surface area of the nonwoven structure were fused. The peel strength is slightly lower than that of Example 1 because the area ratio of the non-woven fabric is low, and the laminated non-woven structure obtained in Example 10 has the same area ratio of 40%. Although the peel strength was excellent because the ratio of the area of all punctate fusion areas to the total surface area of the structure was high, the flexibility was slightly inferior to that of Example 1. Furthermore, the laminated non-woven structure obtained in Example 11 was
The density of the convex projections of the pattern rolls in the ultrasonic fusing device is 9 points / cm ² and the density of the point fusing areas in the non-woven structure is low, so there is some unevenness in peeling strength. The laminated non-woven structure obtained in Example 13 had the same convex protrusion disposition density of 80 points / cm ² and a high density of dot-shaped fused areas in the non-woven structure. Therefore, the flexibility was slightly inferior to that of Example 1. That is, in the laminated non-woven structure of the present invention, the ratio of the area of all dot-like fused areas to the total surface area of the non-woven structure and the density of dot-like fused areas satisfy the above equations (1) and (2). By doing so, it is understood that the tensile strength, peel strength, and flexibility are all improved.

On the other hand, the laminated non-woven structure obtained in Comparative Example 1 was subjected to the partial thermocompression bonding treatment using the hot embossing roller, so that the peel strength was extremely low. That is, in this example, since the natural fibers located at the boundary surface between the long-fiber non-woven fabric layer and the natural-fiber non-woven fabric layer in the spot-shaped fusion-bonded area are not sufficiently fixed in the fused part of the long-fiber, they are not fixed. The peel strength was extremely reduced.
Further, the laminated nonwoven structure obtained in Comparative Example 2 had an area ratio of the convex protrusions of the pattern roll in the ultrasonic fusing device of 1
%, And the ratio of the area of all spot-shaped fused regions to the total surface area of the non-woven structure was too low, so that both tensile strength and peel strength were low. The laminated non-woven structure obtained in Comparative Example 3 had the same area ratio of 45%, and the ratio of the area of all the spot-shaped fused regions to the total surface area of the non-woven structure was too high. Although it was high, it had a high bending resistance and a hard texture. Further, the laminated non-woven structure obtained in Comparative Example 4 had a density of convex protrusions of the pattern rolls of 4 points / cm ² in the ultrasonic fusing device, and the point-shaped fusion of the non-woven structure was confirmed. Since the density of the area was too low, the tensile strength was low, and the peel strength was uneven in the plane of the non-woven structure. The laminated non-woven structure obtained in Comparative Example 5 had the same convex projection disposition density of 90 points / cm ² , and the density of the dot-like fused areas in the non-woven structure was too high. The natural fibers were sufficiently embedded and fixed in the melted portion in the fusion-bonded area formed by melting, and both had high tensile strength and peeling strength, but had high bending resistance and a hard texture.

[0030]

The laminated non-woven structure of the present invention is formed by laminating a long-fiber non-woven fabric layer made of the above-mentioned specific thermoplastic aliphatic polyamide polymer and a non-woven fabric layer in which natural fibers are mechanically entangled. , The long fibers and the natural fibers are fused together to form a point-like fused area, and the natural fibers located at least at the boundary surface between the two non-woven fabric layers in the point-like fused area are fused to the long fibers. It is integrated as a whole by being fixed in a state where it is embedded in the part, and has high tensile strength and peeling strength, excellent dimensional stability and flexibility, dyeability and water absorbency. Further, it has high abrasion resistance and is suitable as a material for medical / sanitary materials, clothing, or life-related materials.

[Brief description of drawings]

FIG. 1 is a schematic view showing a cross section of a dot-like fused area in a laminated nonwoven structure of the present invention.

[Explanation of symbols]

 1: Molten polyamide long fiber layer 2: Natural fiber

Claims (2)

[Claims] 1. A non-woven fabric layer made of long fibers made of a thermoplastic aliphatic polyamide polymer and a non-woven fabric layer made of mechanically entangled natural fibers are laminated, and the long fibers and natural fibers are laminated. In the laminated non-woven structure having a point-like fused area formed by fusing, the natural fibers located at least at the boundary surface between the both non-woven fabric layers in the point-like fused area have a total surface area of the non-woven structure. The ratio A (%) of the area of all the dot-like fused areas to the above and the dot-like fused area density B (dots / cm ² ) satisfy the following formulas (1) and (2), respectively. A laminated non-woven structure characterized by being integrated as a whole by being fixed in a buried state. 2 ≦ A (%) ≦ 40 (1) 7 ≦ B (points / cm ² ) ≦ 80・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (2) 2. The laminated non-woven structure according to claim 1, wherein the single fiber fineness of the long fibers made of the thermoplastic aliphatic polyamide polymer is 1 denier or more and 8 denier or less.