Filament non-woven fabric and manufacturing equipment and manufacturing method thereof

Abstract

The invention relates to a filament non-woven fabric and a manufacturing device and a manufacturing method thereof, the filament non-woven fabric is a fiber net composed of curled filament fibers with a spiral structure, the curled filament fibers are composed of high-melting-point resin and low-melting-point resin, the melting point difference of the high-melting-point resin and the low-melting-point resin is at least 20 DEG C, and at least part of the surface layer of each curled filament fiber is the low-melting-point resin. The low-melting-point resins on the surface layers of the adjacent curled filament fibers are mutually fused and bonded together, and the fluctuation ratio of the air permeability at different positions on the filament non-woven fabric is not more than 10%. Due to the fact that the curled filament fiber net is conveyed to the conveying net curtain or other fiber nets along with rotation of the rotary net, the impact force generated when the curled filament fiber net directly falls onto the conveying net curtain or the previous fiber net is reduced. The phenomenon that fibers of the crimped filament fiber net or the previous fiber net are scattered due to mutual collision when the crimped filament fiber net is in contact with the conveying net curtain or the previous fiber net is prevented, and the defects that the fibers at different positions on the formed filament non-woven fabric are not uniformly distributed and the net surface uniformity is poor can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of nonwoven fabrics, and in particular to a filament nonwoven fabric used for personal care and infant care, and a manufacturing device and a manufacturing method thereof. Background Art

[0002] Filament nonwoven fabric is a nonwoven fabric produced by melt spinning thermoplastic resin. Because of its soft touch and low price, it is often used in sanitary napkins and diapers for personal care and infant care. In order to improve the fluffiness of filament nonwoven fabric, bicomponent fibers composed of low-melting point thermoplastic resin and high-melting point thermoplastic resin are often used. The bicomponent fibers are heated by a heating device. Due to the different thermal shrinkage forces of the two components in the fiber, the fiber curls, thereby improving its fluffiness. However, during the heating process, the low-melting point thermoplastic resin in the fiber will melt, and adjacent fibers will stick together, which affects the curl and curl number of the bicomponent fiber, and does not significantly improve the fluffiness of the filament nonwoven fabric. Summary of the invention

[0003] The purpose of the present invention is to provide a filament nonwoven fabric with good fluffiness and uniform mesh surface and its manufacturing equipment and manufacturing method, so as to overcome the defects of existing products and production methods.

[0004] To achieve the above object, the solution of the present invention is: A filament nonwoven fabric, comprising a fiber web composed of spirally structured curled filament fibers composed of a high-melting point resin and a low-melting point resin with a melting point difference of at least 20°C; the surface layer of the curled filament fibers is at least partially low-melting point resin, and the low-melting point resins on the surface layers of adjacent curled filament fibers are melted and bonded together, wherein: the curl rate of the curled filament fibers is 5% to 30%, the number of curls is 5 to 15 / cm, and the fluctuation rate of air permeability at different positions on the filament nonwoven fabric is not more than 10%.

[0005] The curled filament fibers are eccentric structure filament fibers or parallel structure filament fibers.

[0006] The filament nonwoven fabric has two or more layers of fiber webs, at least one of which is a fiber web composed of curled filament fibers.

[0007] The fluctuation rate of air permeability at different positions on the filament nonwoven fabric is no more than 5%.

[0008] A manufacturing device for filament nonwoven fabrics, used for manufacturing the filament nonwoven fabrics, comprising a hot melt extrusion device, a spinning device, a side blowing cold air device, a spinning drafting device, a cylinder forming machine, a conveying device and a heating device which are sequentially connected to each other; The hot melt extrusion device includes two screw extruders, which are respectively connected to the spinning device; The side-blowing cold air device is located below the spinneret of the spinning device, the spinneret is provided with a double-component spinneret hole, and the side-blowing cold air device is used to blow out the side-blowing cold air on both sides; the spinning drafting device is located below the side-blowing cold air device; the cylinder forming machine is located below the spinning drafting device; The conveying device is located below the cylinder forming machine, and the heating device is located on one side of the conveying device. The conveying device is used to convey the fiber web composed of curly filament fibers with a spiral structure rotated and output by the cylinder forming machine to the heating device for heating and forming.

[0009] The cylinder forming machine comprises a cylinder and a negative pressure suction device; the cylinder can be rotatably arranged below the spinning and stretching device, and the negative pressure suction device is fixed inside the cylinder and is located directly below the spinning and stretching device.

[0010] A method for manufacturing a filament nonwoven fabric, the specific manufacturing steps of which are: Step 1, heating two thermoplastic resins with melting points at least 20°C in a screw extruder respectively, and entering a spinning device after melting, in which the high-temperature thermoplastic resin melt is converted into a melt stream, and then ejected through a two-component spinneret hole on a spinneret, cooled by side-blowing cold air, and stretched through a spinning stretching device to form filament fibers whose surface layer is at least partially a low-melting-point resin; the filament fibers fall down on a cylinder net of a cylinder net-forming machine below the spinning stretching device in a relaxed state to form a filament fiber web, and the filament fiber web leaves the negative pressure suction device of the cylinder net-forming machine as the cylinder net rotates to form a curled filament fiber web with a spiral structure, and is transmitted to a heating device, wherein the curling rate of the curled filament fibers constituting the curled filament fiber web is 5% to 30%, and the number of curls is 5 to 15 / cm; Step 2, the curled filament fiber web is heated by a heating device, the low melting point thermoplastic resin in the curled filament fibers begins to melt and the fibers adhere to each other to form the filament non-woven fabric.

[0011] In the step 1, the two-component spinneret holes on the spinneret plate are eccentric structure spinneret holes or parallel structure spinneret holes.

[0012] The drafting ratio of the filament fibers in the spinning and drafting device is ≥600.

[0013] The wind speed of the filament fibers when reaching the cylinder of the cylinder net-forming machine is 3m / s to 15m / s.

[0014] In the step 1, the spirally structured curled filament fiber web is adsorbed on the flat web forming machine through the negative pressure suction device of the flat web forming machine in a relaxed state as the round web rotates, and then transferred to the heating device.

[0015] Before step 2, one or more layers of the curled filament web formed in step 1 are stacked on the conveying mesh curtain in sequence as the round net rotates to form a multi-layer curled filament web, which is then conveyed to the heating device.

[0016] The cylinder net of the cylinder net-forming machine in step 1 is a metal endless nickel net with an open-pore structure on the surface.

[0017] The heating device in step 2 is a hot air oven or a hot rolling roller.

[0018] In the step 1, the spirally structured curled filament web is transferred to the conveying mesh curtain as the round net rotates, and then transported to the heating device through the conveying mesh curtain; in the step 2, the heating device is a hot air oven; the conveying mesh curtain passes through the hot air oven.

[0019] By adopting the above-mentioned structure and manufacturing method, since the process of stretching the filament fibers in the spinning and drawing device is a process in which the filament fibers are oriented along the direction of external force, and since the orientation degrees and crystallinity of the thermoplastic resins of different components in the filament fibers are different, different internal stresses and curling potential energies exist in the filament fibers during the stretching process. Once the stretching is completed, the filament fibers fall on the circular net of the circular net forming machine below the spinning and drawing device in a relaxed state, and after leaving the negative pressure suction device, a curled filament fiber web composed of filament fibers with a spiral structure is formed; this can effectively prevent the low-melting-point resin in the filament fibers from easily adhering to adjacent fibers during the process of curling the filament fibers after secondary heating after fiber stretching, thereby affecting the curling degree of the filament fibers. and the number of curls; this also improves the fluffiness of the filament non-woven fabric. At the same time, the web-forming machine is a round web-forming machine with a round web structure. When the filament fibers fall on the round web, the filament fibers can be quickly transformed from a stretched state to a state of rotating with the round web, thereby quickly eliminating the force in the vertical direction and accelerating the forming of the fiber spiral structure. At the same time, the curled filament web is transmitted to the conveying mesh curtain or other fiber webs as the round web rotates, reducing the impact force of the curled filament web falling directly onto the conveying mesh curtain or the previous fiber web, preventing the curled filament webs from colliding with each other when contacting the conveying mesh curtain or the previous fiber web and dispersing the fibers of the curled filament web or the previous fiber web, avoiding the defects of uneven fiber distribution at different positions on the formed filament non-woven fabric and poor mesh uniformity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the filament nonwoven fabric in Example 1 of the present invention; Figure 2 This is a schematic diagram of manufacturing the filament nonwoven fabric in Example 1 of the present invention; Figure 3Schematic diagram of a two-component spinneret in Example 1 of the present invention; Figure 4 This is a schematic diagram of manufacturing the filament nonwoven fabric in Example 2 of the present invention; Figure 5 This is a schematic diagram of the manufacturing process of the filament nonwoven fabric in Example 3 of the present invention. DETAILED DESCRIPTION

[0021] In order to further explain the technical solution of the present invention, the present invention is described in detail below through specific embodiments.

[0022] The invention discloses a filament nonwoven fabric and a manufacturing device and a manufacturing method thereof.

[0023] like Figure 1 As shown, the filament non-woven fabric 1 includes a fiber mesh composed of curled filament fibers b with a spiral structure composed of a high-melting point resin and a low-melting point resin with a melting point difference of at least 20°C; the surface layer of the curled filament fibers b is at least partially low-melting point resin, and the low-melting point resins on the surface layers of adjacent curled filament fibers b are melted and bonded to each other.

[0024] Wherein: the curling rate of the curled filament fiber can be 5% to 30%, the number of curls can be 5 to 15 per cm, and the fluctuation rate of the air permeability at different positions on the filament non-woven fabric is no more than 10%.

[0025] See also Figure 2 The present invention also provides a manufacturing device for filament non-woven fabrics, which includes a hot melt extrusion device, a spinning device B, a side-blowing cold air device (not shown), a spinning drafting device E, a round net forming machine F, a conveying device and a heating device which are sequentially connected to each other; the conveying device can be a flat net forming machine or a conveying net curtain I, and the heating device can be a hot air oven J or a hot calender roller.

[0026] The hot melt extrusion device comprises two screw extruders A and A', which are respectively connected to the spinning device B; The side-blowing cold air device is located below the spinneret C of the spinning device B, and the spinneret is provided with a double-component spinneret hole. Figure 3 The two-component spinneret hole can be an eccentric structure spinneret hole N1 or a parallel structure spinneret hole N2.

[0027] The side-blowing cold air device is used to blow out the side-blowing cold air D on both sides; the spinning drafting device E is located below the side-blowing cold air device; the cylinder forming machine F is located below the spinning drafting device E; The conveying device is located below the cylinder forming machine F, and the heating device is located on one side of the conveying device. The conveying device is used to convey the fiber web rotated and output by the cylinder forming machine F to the heating device for heating and forming.

[0028] The present invention is further described below based on the above-mentioned equipment in combination with a specific manufacturing method.

[0029] Example 1 like Figures 2 to 3 As shown, the present invention discloses a filament nonwoven fabric and a manufacturing method thereof, and the specific manufacturing steps are as follows: Step 1: Two thermoplastic resins, high-density polyethylene (HDPE) and polypropylene (PP), with melting points at least 20°C different from each other, are heated in screw extruders A and A', respectively, and after melting, enter a spinning device B, where the high-temperature thermoplastic resin melt is converted into a melt stream, and then ejected through a two-component spinneret hole on a spinneret C, see Figure 3 , wherein: the two-component spinneret hole is an eccentric structure spinneret hole N1 or a parallel structure spinneret hole N2, cooled by side blowing cold air D, and stretched by a spinning stretching device E to form a filament fiber a whose surface layer is at least partially a low-melting-point resin, wherein: the stretching ratio of the filament fiber a is 600, and the filament fiber a falls on the cylinder H of the cylinder net-forming machine F below the spinning stretching device E in a relaxed state to form a filament fiber net, and the filament fiber net leaves the negative pressure suction device G of the cylinder net-forming machine F as the cylinder net F rotates to form a curled filament fiber net b with a spiral structure, and is transmitted to the conveying net curtain I, wherein the wind speed of the filament fiber a when arriving at the cylinder H of the cylinder net-forming machine F is 3m / s, and the curling rate of the curled filament fiber constituting the curled filament fiber net b is 5% to 30%, and the number of curls is 5 to 15 / cm; In step 2, the curled filament web b is conveyed to the hot air oven J for heating by passing through the conveying mesh curtain I of the hot air oven J. The low melting point thermoplastic resin in the curled filament fibers begins to melt and the fibers adhere to each other to form the filament non-woven fabric 1.

[0030] Fiber curl and crimp number detection Test instrument: Curl elasticity tester YG362B Test sample: Fiber bundle Test steps: 1) Calibrate the instrument, use the upper clamp to take out a fiber, and use tweezers to place the other end of the fiber in the middle of the lower clamp jaws and clamp it.

[0031] 2) Turn on the brake knob, apply a light load of 0.02mN / dtex, and press the "down" key. The balance light turns on and the down light turns off. The display shows L0 (light load elongation length). Turn the "25mm length pointer" on the top of the lower clamp to calculate the number of crimps through the magnifying glass. The number of crimps is: (left crest number + right crest number) / 2.

[0032] 3) Rotate the reading button, load a heavy load of 1.0mN / dtex, and press the "down" key. The balance light turns on and the down light turns off. The J value displayed on the display is the curl degree.

[0033] The above-mentioned fiber curling rate and curling number detection method is used to detect the curling number and curling degree of the filament fiber a after leaving the negative pressure suction device G of the cylinder net forming machine F. The curling rate of the curled filament fiber with a spiral structure is 20%, and the curling number is 10 / cm. Since the process of the filament fiber being stretched in the spinning and drawing device is the process of the filament fiber being oriented along the direction of the external force, and since the orientation degree and crystallinity of the thermoplastic resin of different components in the filament fiber are different, different internal stresses and curling potential energies exist in the filament fiber during the stretching process. Once the stretching is completed, when the filament fiber falls on the cylinder net H of the cylinder net forming machine F below the spinning and drawing device E in a relaxed state, a curled filament fiber web b composed of curled filament fibers with a spiral structure is formed after leaving the negative pressure suction device G. In this way, there is no need to curl the filament fiber by heating it again, which can solve the problem that the low melting point resin in the filament fiber is easy to adhere to the adjacent fibers during the reheating process, thereby affecting the full curling of the two-component fiber. At the same time, the curl degree of the filament fiber can be adjusted by adjusting the draft ratio of the filament fiber.

[0034] Breathability Test instrument: FX3300-Ⅳ air permeability tester.

[0035] 1. Set the area to 38cm 2 Install the clamp arm on the upper test head and connect the high-pressure rubber tube to the test head. 2 The lower test head is fixed in the specimen diameter setting circle and the high-pressure rubber tube is connected to the lower test head.

[0036] 2. Set the experimental conditions: Unit selection: m 3 / m 2 *Min test pressure: 125 Pa.

[0037] 3. Place the front side of the filament non-woven fabric flat on the lower test head, press the clamp arm to start the test, and when the indicator light of the correct test range tends to be stable and displays green, the reading is the air permeability of the filament non-woven fabric. Test the air permeability of the filament non-woven fabric at different positions, and record and calculate the air permeability fluctuation rate of the filament non-woven fabric.

[0038] Volatility (%) = standard deviation / mean value × 100% The test data is as follows:

[0039] Whether the non-woven fabric mesh surface is uniform is an important criterion for measuring the quality of non-woven fabrics. Due to the low thickness of filament non-woven fabrics, the mesh uniformity of filament non-woven fabrics can be measured by testing the air permeability of different positions of the filament non-woven fabrics and calculating the fluctuation rate of the air permeability.

[0040] By using the above-mentioned air permeability fluctuation test method, the air permeability fluctuation at different positions on the filament nonwoven fabric in this embodiment 1 is only 3.30%, mainly because the curled filament fiber web b is transmitted to the conveying net curtain I with the rotation of the round net H, which reduces the impact force of the curled filament fiber web b directly falling on the conveying net curtain I, and prevents the curled filament fiber web b from colliding with each other when contacting the conveying net curtain I and breaking up the curled filament fiber web b, which can avoid the defects of uneven fiber distribution at different positions on the formed filament nonwoven fabric 1 and poor mesh uniformity. And due to the presence of the round net H, when the filament fiber a falls on the round net H, the filament fiber a can be quickly transformed from a stretched state to rotate with the round net H, thereby quickly eliminating the vertical force and accelerating the formation of the fiber spiral structure, and the round net I is a metal endless nickel net with an open-pore structure on the surface, and its surface is smooth, not easy to get stuck, and prevents the long fiber from breaking.

[0041] In addition, in this embodiment 1, the conveying mesh curtain I passes through the hot air oven J, and the fiber web does not need to be transferred to different conveying mesh curtains multiple times, so that the formed filament non-woven fabric has a more uniform mesh surface, and the fibers are heated by the hot air oven J to melt and adhere to each other through the low-melting point resin on the surface of the curled filament fibers to form a filament non-woven fabric, which greatly reduces the hot rolling melting point area, and the formed filament non-woven fabric has better air permeability.

[0042] Example 2 like Figure 4 The invention discloses a filament nonwoven fabric and a method for manufacturing the same. The specific manufacturing steps are as follows: Step 1, two thermoplastic resins, high-density polyethylene (HDPE) and polyethylene terephthalate (PET), whose melting points differ by at least 20° C., are heated in screw extruders A and A', respectively, and after melting, enter a spinning device B, and the high-temperature thermoplastic resin melt is converted into a melt stream in the spinning device B, and then ejected through a two-component spinneret hole on a spinneret C, wherein: the two-component spinneret hole can be an eccentric structure spinneret hole or a parallel structure spinneret hole, cooled by side blowing cold air D, and stretched by a spinning stretching device E to form a filament fiber a whose surface layer is at least partially a low-melting-point resin, wherein: the stretching ratio of the filament fiber is 720, and the filament fiber a is in a relaxed state The filament fiber web b is a spiral filament fiber web formed by a spiral structure and falls on the cylinder H of the cylinder web forming machine F below the spinning drafting device E in a relaxed state. The filament fiber web leaves the negative pressure suction device G of the cylinder web forming machine F as the cylinder web F rotates, and forms a curled filament fiber web b with a spiral structure. The curled filament fiber web b rotates with the cylinder web H and then passes through the negative pressure suction device L in the flat web forming machine K in a relaxed state to be adsorbed on the flat web forming machine K and transmitted to the heating device. The wind speed of the filament fiber a when reaching the cylinder H of the cylinder web forming machine F is 8 m / s, and the curling rate of the curled filament fiber constituting the curled filament fiber web b is 25%, and the number of curls is 15 / cm. In step 2, the curled filament web b is transferred to the hot rolling roller M located behind the flat mesh web forming machine K for hot rolling. The low melting point thermoplastic resin in the curled filament fibers begins to melt and the fibers adhere to each other. At the same time, the curled filament web b is hot pressed under the action of the hot rolling roller to form a plurality of hot rolling point consolidated mesh surfaces, thereby forming the filament non-woven fabric 1.

[0043] The air permeability at different positions of the filament nonwoven fabric 1 in this embodiment 2 was measured and the fluctuation rate was calculated. The test results are as follows:

[0044] In the present embodiment 2, the filament fiber a is formed into a curled filament fiber net b composed of filament fibers with a spiral structure after the cylinder net forming machine F, and then the curled filament fiber net b enters the flat net forming machine K in a relaxed state as the cylinder net rotates and is transported to the heating device, the flat net forming machine K not only positions and transmits the fiber on the mesh belt surface according to a predetermined distribution law, but also enables the curled filament fiber net b to fully relax and curl, and the curling degree and curling number formed are larger, so that the filament non-woven fabric formed is more fluffy. In addition, the hot rolling roller is used for fixed net forming, and the surface has a hot rolling point, so that the bonding strength of the filament non-woven fabric is larger, and the mechanical properties of the non-woven fabric are better, but the air permeability of the filament non-woven fabric can be reduced. Of course, the hot air drying oven can also be used to make the curled fiber net consolidated and formed, so that the fluffiness of the filament non-woven fabric can be better improved, and the air permeability of the filament non-woven fabric is not affected.

[0045] Example 3 like Figure 5As shown, the present invention discloses a filament nonwoven fabric and a manufacturing method thereof, and the specific manufacturing steps are as follows: (1) Two thermoplastic resins, high-density polyethylene (HDPE) and polypropylene (PP), whose melting points differ by at least 20°C, are heated in screw extruders A1 and A1', respectively, and after melting, enter a spinning device B1, where the high-temperature thermoplastic resin melt is converted into a melt stream, and then ejected through a two-component spinneret hole on a spinneret C1, wherein the two-component spinneret hole is an eccentric spinneret hole or a parallel spinneret hole, cooled by side-blowing cold air D1, and stretched by a spinning stretching device E1 to form a filament fiber a whose surface layer is at least partially a low-melting-point resin , wherein: the draft ratio of the filament fiber is 680, the filament fiber a falls on the flat mesh web-forming machine K below the spinning drafting device E in a relaxed state to form a filament fiber web, and the filament fiber web leaves the negative pressure suction device L of the flat mesh web-forming machine K to form a curled filament fiber web b1 with a spiral structure, and is transmitted to the conveying mesh curtain I, wherein the wind speed of the filament fiber a1 when reaching the mesh curtain of the flat mesh web-forming machine K is 12m / s, the curling rate of the curled filament fiber constituting the curled filament fiber web b1 is 5%, and the number of curls is 8 / cm; (2) Two thermoplastic resins, high-density polyethylene (HDPE) and polyethylene terephthalate (PET), whose melting points differ by at least 20°C, are heated in screw extruders A and A', respectively, and after melting, enter a spinning device B, where the high-temperature thermoplastic resin melt is converted into a melt stream, and then ejected through a two-component spinneret hole on a spinneret C, wherein the two-component spinneret hole is an eccentric spinneret hole or a parallel spinneret hole, cooled by side-blowing cold air D, and stretched by a spinning stretching device E to form a filament fiber a whose surface layer is at least partially a low-melting-point resin, wherein the stretching ratio of the filament fiber is 720, and the filament fiber a is in a relaxed state The filament fiber web is formed on the cylinder H of the cylinder web forming machine F below the spinning drafting device E, and the filament fiber web leaves the negative pressure suction device G of the cylinder web forming machine F as the cylinder web F rotates to form a curled filament fiber web b with a spiral structure, and the curled filament fiber web b is stacked on the previous curled filament fiber web b1 on the conveying net curtain I as the cylinder web rotates to form a multi-layer curled filament fiber web, and is conveyed to the heating device, wherein the wind speed of the filament fiber a when reaching the cylinder H of the cylinder web forming machine F is 15m / s, the curling rate of the curled filament fiber constituting the curled filament fiber web b is 15%, and the number of curls is 10 / cm; (3) The multi-layer curled filament fiber web is hot-rolled by a hot rolling roller M, and the low-melting-point thermoplastic resin in the curled filament fibers begins to melt and the fibers adhere to each other. At the same time, the curled filament fiber web b is hot-pressed under the action of the hot rolling roller to form a plurality of hot rolling point consolidation mesh surfaces, thereby forming the filament non-woven fabric 1.

[0046] The air permeability at different positions of the filament nonwoven fabric 1 in this embodiment 3 was measured and the fluctuation rate was calculated. The test results are as follows:

[0047] By adopting the above-mentioned structure and manufacturing method, since the curled filament fiber web b is formed into a uniform and continuous fiber web by the rotary screen web-forming machine F from the disordered filament fibers and then compounded with the previous curled filament fiber web b1, the rotary screen web-forming machine F not only positions and transmits the fibers on the mesh belt surface according to a predetermined distribution pattern, but also separates the filament fibers from the drawing airflow, thereby minimizing the interference effect on the curled filament fiber web b already on the rotary screen H, that is, effectively preventing the drawing airflow in the spinning process from blowing away the fibers in the curled filament fiber web b, thereby ensuring that the formed filament non-woven fabric has a uniform and fluffy mesh surface.

[0048] The above-mentioned manufacturing method can be used to manufacture multi-layer filament non-woven fabrics. The previous curled filament fiber web b1 can be formed by a flat mesh web-forming machine K or a round mesh web-forming machine (the flat mesh web-forming machine K is taken as an example in this embodiment), and the second layer and above curled filament fiber webs are respectively formed into uniform and continuous fiber webs by corresponding round mesh web-forming machines with messy filament fibers. Then, in a relaxed state, they are successively stacked on the previous curled filament fiber web as the round mesh rotates to form multi-layer curled filament fiber webs, which are then transferred and stacked on other fiber webs through the rotation of the round mesh, thereby reducing the impact force of the curled filament fiber web directly falling onto the previous fiber web, preventing the curled filament fiber webs from colliding with each other when contacting the previous fiber web and dispersing the fibers of the previous fiber web, effectively solving the problems of uneven fiber distribution at different positions on the formed multi-layer filament non-woven fabric and poor mesh surface uniformity.

[0049] In addition, the resin used for the two layers of curled filament fiber webs b and b1 of the filament non-woven fabric 1 in this embodiment 3 can be selected according to the specific application of the non-woven fabric. In this embodiment 3, the curled filament fiber web b1 adopts HDPE / PP, and the curled filament fiber web b adopts HDPE / PET. Since the fibers formed by HDPE / PP are softer, and the fibers formed by HDPE / PET have a certain stiffness, the surface of the formed filament non-woven fabric 1 is softer and the fluffiness is better.

Claims

1. A filament nonwoven fabric, characterized in that: The filament non-woven fabric comprises a fiber web composed of spirally structured curled filament fibers composed of a high-melting point resin and a low-melting point resin with a melting point difference of at least 20°C; the surface layer of the curled filament fibers is at least partially low-melting point resin, and the low-melting point resins on the surface layers of adjacent curled filament fibers are melted and bonded together, wherein: the curl rate of the curled filament fibers is 5% to 30%, the number of curls is 5 to 15 / cm, and the fluctuation rate of the air permeability at different positions on the filament non-woven fabric is not more than 10%.

2. The filament nonwoven fabric according to claim 1, characterized in that: The curled filament fibers are eccentric structure filament fibers or parallel structure filament fibers.

3. The filament nonwoven fabric according to claim 1, characterized in that: The filament nonwoven fabric has two or more layers of fiber webs, at least one of which is a fiber web composed of curled filament fibers.

4. The filament nonwoven fabric according to claim 1, characterized in that: The fluctuation rate [1] of the air permeability at different positions on the filament non-woven fabric is no more than 5%.

5. A manufacturing device for a filament nonwoven fabric, used for manufacturing a filament nonwoven fabric according to any one of claims 1 to 4, characterized in that: It includes a hot melt extrusion device, a spinning device, a side-blowing cold air device, a spinning drafting device, a cylinder forming machine, a conveying device and a heating device which are connected to each other in sequence; The hot melt extrusion device includes two screw extruders, which are respectively connected to the spinning device; The side-blowing cold air device is located below the spinneret of the spinning device, the spinneret is provided with a double-component spinneret hole, and the side-blowing cold air device is used to blow out the side-blowing cold air on both sides; the spinning drafting device is located below the side-blowing cold air device; the cylinder forming machine is located below the spinning drafting device; The conveying device is located below the cylinder forming machine, and the heating device is located on one side of the conveying device. The conveying device is used to convey the fiber web composed of curly filament fibers with a spiral structure rotated and output by the cylinder forming machine to the heating device for heating and forming.

6. The manufacturing equipment of a filament nonwoven fabric according to claim 5, characterized in that: The cylinder forming machine comprises a cylinder and a negative pressure suction device; the cylinder can be rotatably arranged below the spinning and stretching device, and the negative pressure suction device is fixed inside the cylinder and is located directly below the spinning and stretching device.

7. A method for producing a filament nonwoven fabric, characterized in that: The specific manufacturing steps are: Step 1, heating two thermoplastic resins with melting points at least 20°C in a screw extruder respectively, and entering a spinning device after melting, converting the thermoplastic resin melt into a melt stream in the spinning device, and then ejecting it through a two-component spinneret hole on a spinneret, cooling it by side blowing cold air, and stretching it through a spinning stretching device to form filament fibers whose surface layer is at least partially a low-melting-point resin; the filament fibers fall down on a cylinder net of a cylinder net-forming machine below the spinning stretching device in a relaxed state to form a filament fiber web, and the filament fiber web leaves the negative pressure suction device of the cylinder net-forming machine as the cylinder net rotates to form a curled filament fiber web with a spiral structure, and is transmitted to a heating device, wherein the curling rate of the curled filament fibers constituting the curled filament fiber web is 5% to 30%, and the number of curls is 5 to 15 / cm; Step 2, the curled filament fiber web is heated by a heating device, the low melting point thermoplastic resin in the curled filament fibers begins to melt and the fibers adhere to each other to form the filament non-woven fabric.

8. The method for producing a filament nonwoven fabric according to claim 7, wherein: In the step 1, the two-component spinneret holes on the spinneret plate are eccentric structure spinneret holes or parallel structure spinneret holes.

9. The method for producing a filament nonwoven fabric according to claim 7, wherein: The drafting ratio of the filament fibers in the spinning and drafting device is ≥600.

10. The method for producing a filament nonwoven fabric according to claim 7, wherein: The wind speed of the filament fibers when reaching the cylinder of the cylinder net-forming machine is 3m / s to 15m / s.

11. The method for producing a filament nonwoven fabric according to claim 7, wherein: In the step 1, the spirally structured curled filament fiber web is adsorbed on the flat web forming machine by the negative pressure suction device in the flat web forming machine in a relaxed state as the round web rotates, and then transferred to the heating device.

12. The method for producing a filament nonwoven fabric according to claim 7, wherein: Before step 2, one or more layers of the curled filament web formed in step 1 are stacked on the conveying mesh curtain in sequence as the round net rotates to form a multi-layer curled filament web, which is then conveyed to the heating device.

13. The method for producing a filament nonwoven fabric according to claim 7, wherein: The cylinder net of the cylinder net-forming machine in step 1 is a metal endless nickel net with an open-pore structure on the surface.

14. The method for producing a filament nonwoven fabric according to claim 7, wherein: The heating device in step 2 is a hot air oven or a hot rolling roller.

15. The method for producing a filament nonwoven fabric according to claim 7, wherein: In the step 1, the spirally structured curled filament web is transferred to the conveying mesh curtain as the round net rotates, and then transported to the heating device through the conveying mesh curtain; in the step 2, the heating device is a hot air oven; the conveying mesh curtain passes through the hot air oven.

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