Meltblown nonwoven fabric, multilayer spunbond nonwoven fabric containing the same, and method for producing the same

Abstract

The present invention relates to a meltblown nonwoven fabric, a multi-layered spunbonded nonwoven fabric including the same, and a manufacturing method thereof. The present invention relates to a meltblown nonwoven fabric that is not only environmentally friendly because it uses recycled polyester flakes, but also has excellent rigidity, sound absorption properties and compressive elasticity, and is a material used for automotive sound absorbing materials, and can be used for automotive internal materials such as wheel guards and trunk trims that require rigidity, sound absorption properties and compressive elasticity, and a multi-layered spunbonded nonwoven fabric including the same, and a manufacturing method thereof.

Description

Technical Field

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[0003]

[0001] The present invention relates to a melt-blown non-woven fabric, a multi-layered spunbond non-woven fabric containing the same, and a method for manufacturing the same. The present invention uses recycled polyester flakes, which is not only environmentally friendly but also excellent in rigidity, sound absorption, and compression elastic modulus, and is a material used for automotive sound absorption materials. It can be used for automotive interior materials such as wheel guards and trunk trims in automobiles that require rigidity, sound absorption, and compression elastic modulus, and relates to a melt-blown non-woven fabric, a multi-layered spunbond non-woven fabric containing the same, and a method for manufacturing the same.

Background Art

[0002] For the purpose of sound insulation and sound absorption in automobiles, various forms of non-woven fabric formulations are applied to automobiles. In many cases, parts in the form of carpets, headlinings, etc. coated with films such as ethylene vinyl acetate (EVA), polyethylene (PE), polypropylene (PP), etc. are applied for the purposes of sound absorption, sound insulation, waterproofing, dustproofing, and molding processability. Such parts can hardly be recycled in the case of waste materials generated after the scrapping of automobiles, defective products generated during the manufacturing process, and scraps generated after product molding, and are currently being treated as heat sources in places such as cement firing and co-generation power plants.

[0003] In particular, for quiet automobile operation, in order to reduce the noise generated from the wheels during driving, the wheel guard material is converted from a conventional olefin-based polymer injection molded product to a non-woven fabric composite product utilizing fibers. However, due to the problem of increased component costs compared to olefin-based polymer molded products, there are limitations in generalization. Also, the cotton weight of general non-woven fabrics for automobile wheel guards is generally 800 to 1600 g per square meter. The use of such non-woven fabrics has a higher weight, a more complex manufacturing process, an increase in the manufacturing cost of parts, and is limitedly applied to high-class vehicle models compared to the conventional injection type.

[0004] [[ID=B]] In addition, various other technologies have been reported for recycling used automotive carpets and carpet scraps.

[0005] Previously, Korean Published Patent No. 2013-0005593 disclosed a sound-absorbing and sound-insulating material manufactured by finely crushing waste sheets, mixing polyester fibers, low-melting-point polyester fibers, polypropylene fibers, and hemp into the resulting pulverized material, and then cutting it. However, when manufacturing by mixing urethane foam with polyester fibers, there is a problem of insufficient rigidity because materials with different shapes are bonded together with a low-melting-point polyester binder. In addition, although there is a needle punching step in the process, entanglement occurs between the fibers rather than between the urethane foam and fibers, resulting in insufficient overall rigidity of the recycled sound-absorbing material. This limits its applications, such as being used in sound-absorbing parts that do not require rigidity when applied to automobiles. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The present invention was made to solve the aforementioned problems, and its purpose is to provide a meltblown nonwoven fabric, a multilayer spunbond nonwoven fabric containing the same, and a method for manufacturing the same, which is not only environmentally friendly using recycled polyester flakes, but also has excellent rigidity, sound absorption and compressive modulus, and is a material that can be used as a sound-absorbing material for automobiles, and can be used in automotive internal materials such as wheel guards and trunk trims that require rigidity, sound absorption and compressive modulus. [Means for solving the problem]

[0007] To solve the aforementioned problems, the present invention may include a method for producing a meltblown nonwoven fabric, comprising: a first step of crushing polyester flakes to produce polyester flake powder; a second step of heating the polyester flake powder to crystallize it; a third step of melting the crystallized polyester flake powder to produce a molten material; and a fourth step of spinning the molten material to produce meltblown fibers, and laminating the produced fibers to produce a meltblown nonwoven fabric.

[0008] In a preferred embodiment of the present invention, the molten product prepared in the third step may contain 0.3 to 3.0 mol% isophthalic acid (IPA).

[0009] In a preferred embodiment of the present invention, the polyester flakes may include one or more selected from polyethylene terephthalate (PET) flakes, polytetramethylene terephthalate (PTT) flakes, polybutylene terephthalate (PBT) flakes, and polypropylene (PP) flakes.

[0010] In a preferred embodiment of the present invention, the flake powder produced in the first step may have an average particle size of 1 to 10 mm.

[0011] In a preferred embodiment of the present invention, the second heating stage can be performed at a temperature of 100 to 180°C.

[0012] In a preferred embodiment of the present invention, the molten product produced in the third step may have an intrinsic viscosity (IV) of 0.40 to 0.60 dl / g.

[0013] In a preferred embodiment of the present invention, the meltblown fibers produced in the fourth step may have an average diameter of 0.5 to 20 μm.

[0014] In a preferred embodiment of the present invention, the meltblown nonwoven fabric produced in the fourth step may have a basis weight of 100 to 900 gsm.

[0015] The meltblown nonwoven fabric of the present invention may contain 0.3 to 3.0 mol% isophthalic acid (IPA) and have a basis weight of 100 to 900 gsm.

[0016] In a preferred embodiment of the present invention, the meltblown nonwoven fabric of the present invention may be manufactured by spinning a molten polyester flake.

[0017] In a preferred embodiment of the present invention, the meltblown nonwoven fabric of the present invention may be composed of meltblown fibers having an average diameter of 0.5 to 20 μm.

[0018] In a preferred embodiment of the present invention, the meltblown nonwoven fabric of the present invention may have a stiffness of 1.3 to 1.5 MPa when measured according to KS M 6518.

[0019] Furthermore, the multilayer spunbond nonwoven fabric of the present invention is a multilayer spunbond nonwoven fabric having a spunbond nonwoven fabric as the outermost layer and at least one meltblown nonwoven fabric layer as an inner layer, wherein the meltblown nonwoven fabric layer may include the meltblown nonwoven fabric of the present invention as described above. In this case, the multilayer spunbond nonwoven fabric may also be used as an automotive sound-absorbing material.

[0020] The terms used in this invention will be explained below. In this invention, the term "fiber" as used means "yarn" or "thread," and refers to various types of ordinary threads and fibers. [Effects of the Invention]

[0021] The melt-blown nonwoven fabric of the present invention, the multi-layer structured spunbond nonwoven fabric containing the same, and the manufacturing method thereof are not only environmentally friendly by using recycled polyester flakes, but also excellent in rigidity, sound absorption, and compression elastic modulus, and are materials used for automotive sound-absorbing materials, and can be utilized for automotive built-in materials such as wheel guards and trunk trims of automobiles that require rigidity, sound absorption, and compression elastic modulus.

Embodiments for Carrying Out the Invention

[0022] Hereinafter, with reference to the accompanying drawings, a person having ordinary knowledge in the technical field to which the present invention pertains will be described in detail so that the embodiments of the present invention can be easily implemented. The present invention can be embodied in various different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts not related to the explanation are omitted, and the same reference numerals are added to the same or similar components throughout the specification.

[0023] The manufacturing method of the melt-blown nonwoven fabric of the present invention includes the first to fourth steps.

[0024] First, in the first step of the manufacturing method of the melt-blown nonwoven fabric of the present invention, polyester flakes can be pulverized to produce polyester flake powder. At this time, the polyester flakes may include one or more selected from polyethylene terephthalate (PET) flakes, polytrimethylene terephthalate (PTT) flakes, polybutylene terephthalate (PBT) flakes, and polypropylene (PP) flakes, and preferably may include polyethylene terephthalate (PET) flakes.

[0025] In addition, the polyester flakes of the present invention may be manufactured by separating them from waste carpets and waste felt scraps.

[0026] In addition, the average particle size of the polyester flake powder produced by pulverization may be 1 to 10 mm, preferably 2 to 7 mm, and more preferably 3 to 6 mm. If the average particle size is less than 1 mm, a large amount of dust will be generated during the manufacturing process, which may cause dust pollution and health problems for workers. Fine particles of polyester flake powder will enter the Dead Space in the EXT' during the melting process, which may cause problems such as the generation of carbide and foreign matter in the PET melt. If it exceeds 10 mm, hunting may occur during the operation of the EXT' due to the relatively large particle size of the powder.

[0027] Next, the second step of the method for manufacturing the melt blown nonwoven fabric of the present invention is that the polyester flake powder produced in the first step can be heated and crystallized. At this time, the heating can be carried out at a temperature of 100 to 180 °C, preferably 120 to 160 °C, and more preferably 130 to 150 °C. If the heating temperature is less than 100 °C, the removal of moisture in the flake powder is not uniform, resulting in variations in the moisture content within the powder. When the moisture content is high, hydrolysis will occur during the melting process, and problems such as a decrease in mobility due to Polymer Drip may occur during the spinning process. If it exceeds 180 °C, the flakes will aggregate with each other during the crystallization stage, resulting in non-uniform crystallization and drying. In severe cases, equipment failure may occur due to overloading in the crystallization equipment.

[0028] Next, the third step of the method for manufacturing the melt blown nonwoven fabric of the present invention is that the polyester flake powder crystallized in the second step can be melted to produce a melt. In this case, the molten material may contain 0.3 to 3.0 mol%, preferably 0.5 to 2.5 mol%, of isophthalic acid (IPA). If the isophthalic acid (IPA) content is less than 0.3 mol%, the fineness of the fibers within the nonwoven fabric increases due to the increase in viscosity and melting point, and because the solidification rate is relatively fast, there is a problem that the strength of the nonwoven fabric decreases. If it exceeds 3.0 mol%, the viscosity and melting point decrease, resulting in non-uniformity of the fineness of the nonwoven web. In this case, if the non-uniformity increases, there is a problem that partial differences in sound absorption performance in the low-frequency range may occur. The melting temperature can be a temperature that can melt the crystallized polyester flake powder, and is preferably 240 to 320°C.

[0029] Furthermore, the molten material produced in the third stage may have an intrinsic viscosity (IV) of 0.40 to 0.60 dl / g, preferably 0.45 to 0.55 dl / g. If the intrinsic viscosity of the molten material is less than 0.40 dl / g, problems such as uneven fineness due to low viscosity and poor mobility due to polymer drip may occur. If it exceeds 0.60 dl / g, the high viscosity may result in uneven polymer flow within the meltblown nozzle, causing variations in fineness, as well as nozzle hole clogging where the holes in the meltblown nozzle are partially blocked.

[0030] Finally, the fourth step of the method for producing meltblown nonwoven fabric according to the present invention is to spin the molten material produced in the third step to produce meltblown fibers, and then laminate the produced fibers to produce meltblown nonwoven fabric.

[0031] The aforementioned spinning can be performed using a meltblown spinning die, and the spinning can be carried out at a spinning temperature of 260-280°C. Furthermore, immediately after spinning, meltblown fibers can be produced by solidifying the material with high-pressure hot air at 250-290°C, preferably 260-280°C.

[0032] The manufactured meltblown fibers may have an average diameter of 0.5 to 20 μm, preferably 1.0 to 10 μm. If the average diameter is less than 0.5 μm, the solidification rate is fast due to the fineness, making it difficult to form a nonwoven fabric. Even if a nonwoven fabric is formed, there may be a problem with insufficient strength. If it exceeds 20 μm, there may be a problem with insufficient sound absorption performance in the high-frequency range.

[0033] Furthermore, the manufactured meltblown nonwoven fabric may have a basis weight of 100 to 900 gsm, preferably 500 to 900 gsm, and more preferably 600 to 800 gsm. If the basis weight of the meltblown nonwoven fabric is less than 100 gsm, there may be a problem of insufficient sound absorption performance in the low-frequency range due to insufficient weight, and if it exceeds 900 gsm, not only will there be assembly problems due to the increased volume of the nonwoven fabric, but the high weight of the nonwoven fabric may also lead to a decrease in the fuel efficiency of the automobile.

[0034] Furthermore, the meltblown nonwoven fabric of the present invention may be manufactured through the method for manufacturing the meltblown nonwoven fabric of the present invention described above.

[0035] Specifically, the meltblown nonwoven fabric of the present invention may be a meltblown nonwoven fabric manufactured by spinning a molten material of polyester flakes. In this case, the meltblown nonwoven fabric may contain 0.3 to 3.0 mol%, preferably 0.5 to 2.5 mol%, of isophthalic acid (IPA), and may have a basis weight of 100 to 900 gsm, preferably 500 to 900 gsm, and more preferably 600 to 800 gsm.

[0036] As a more specific example, when the basis weight of the meltblown nonwoven fabric of the present invention is 100 to 700 gsm, preferably 550 to 650 gsm, it may contain 0.3 to 0.9 mol%, preferably 0.3 to 0.7 mol%, of isophthalic acid (IPA). When the basis weight of the meltblown nonwoven fabric of the present invention is 700 to 900 gsm, preferably 750 to 850 gsm, it may contain 1.5 to 3.0 mol%, preferably 2.3 to 2.7 mol%, of isophthalic acid (IPA).

[0037] Furthermore, the meltblown nonwoven fabric of the present invention may be composed of meltblown fibers having an average diameter of 0.5 to 20 μm, preferably 1.0 to 10 μm, and more preferably 1.0 to 5 μm. As a more specific example, when the basis weight of the meltblown nonwoven fabric of the present invention is 100 to 700 gsm, preferably 550 to 650 gsm, the meltblown nonwoven fabric of the present invention may be composed of meltblown fibers having an average diameter of 0.5 to 10 μm, preferably 0.5 to 5 μm, and more preferably 0.7 to 2 μm. When the basis weight of the meltblown nonwoven fabric of the present invention is 700 to 900 gsm, preferably 750 to 850 gsm, the meltblown nonwoven fabric of the present invention may be composed of meltblown fibers having an average diameter of 5 to 20 μm, preferably 8 to 15 μm, and more preferably 8 to 12 μm.

[0038] Furthermore, the meltblown nonwoven fabric of the present invention may have a rigidity of 1.3 to 1.5 MPa, preferably 1.33 to 1.45 MPa, when measured according to KS M 6518.

[0039] Furthermore, the multilayer spunbond nonwoven fabric of the present invention may contain one or more layers of the meltblown nonwoven fabric of the present invention as described above.

[0040] Specifically, the multilayer spunbond nonwoven fabric of the present invention is a nonwoven fabric having a spunbond nonwoven fabric as the outermost layer and at least one meltblown nonwoven fabric layer as an inner layer, wherein the meltblown nonwoven fabric layer may include the meltblown nonwoven fabric of the present invention.

[0041] The basic nonwoven fabric structure of the multilayer spunbond nonwoven fabric of the present invention may consist of multiple layers in the form of spunbond nonwoven fabric / meltblown nonwoven fabric / spunbond nonwoven fabric, where the spunbond nonwoven fabric layer forming the outer layer can consist of one or more layers, and the internal meltblown nonwoven fabric layer can also consist of one or more layers, and the number of layers is not limited. Such a multilayer spunbond nonwoven fabric of the present invention can be called an "SMS-type nonwoven fabric".

[0042] Furthermore, the meltblown nonwoven fabric of the present invention can be used as a sound-absorbing material, and preferably as a sound-absorbing material for automobiles.

[0043] Furthermore, the multilayer spunbond nonwoven fabric of the present invention can be used as a sound-absorbing material, and preferably as a sound-absorbing material for automobiles.

[0044] The present invention has been described above, primarily focusing on examples. However, these are merely illustrative and do not limit the embodiments of the present invention. A person with ordinary skill in the art to which the embodiments of the present invention belong will understand that various modifications and applications not exemplified above are possible without departing from the essential characteristics of the present invention. For example, each component specifically shown in the embodiments of the present invention can be modified and implemented. Furthermore, any differences related to such modifications and applications should be understood to be included within the scope of the present invention as defined in the appended claims.

[0045] Example 1: Manufacturing of meltblown nonwoven fabric (1) PET flakes manufactured using isophthalic acid as one of the raw materials were crushed to produce PET flake powder with an average particle size of 4 mm. (2) The manufactured PET flake powder was placed in a crystallization apparatus and heated at a temperature of 140°C under stirring to crystallize the PET flake powder. (3) The crystallized PET flake powder was heated to 280°C to melt it and produce a PET molten product containing 0.5 mol% isophthalic acid (IPA). The produced PET molten product was passed through a screen filter to remove impurities and produced a PET molten product with an intrinsic viscosity (IV) of 0.50 dl / g. (4) The molten PET material was fed into a meltblown spinning die and spun at a spinning temperature of 270°C. After solidification with high-pressure hot air at 270°C, meltblown fibers with an average diameter of 1 μm were produced. The produced fibers were then laminated to produce a meltblown nonwoven fabric, which is a self-bonding nonwoven fabric with a basis weight of 600 gsm.

[0046] Example 2: Manufacturing of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 1. However, unlike in Example 1, when the PET flake powder was crystallized in step (2), it was heated to a temperature of 90°C to ultimately produce the meltblown nonwoven fabric.

[0047] Example 3: Manufacturing of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 1. However, unlike in Example 1, when the PET flake powder was crystallized in step (2), it was heated to a temperature of 190°C to ultimately produce the meltblown nonwoven fabric.

[0048] Example 4: Production of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 1. However, unlike in Example 1, when manufacturing meltblown fibers in step (4), meltblown fibers with an average diameter of 0.2 μm were manufactured, and a meltblown nonwoven fabric was ultimately produced.

[0049] Example 5: Production of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 1. However, unlike in Example 1, when manufacturing meltblown fibers in step (4), meltblown fibers with an average diameter of 10 μm were manufactured, and a meltblown nonwoven fabric was ultimately produced.

[0050] Example 6: Production of meltblown nonwoven fabric (1) PET flakes manufactured using isophthalic acid as one of the raw materials were crushed to produce PET flake powder with an average particle size of 4 mm. (2) The manufactured PET flake powder was placed in a crystallization apparatus and heated at a temperature of 140°C under stirring to crystallize the PET flake powder. (3) The crystallized PET flake powder was heated to 280°C to melt it and produce a PET molten product containing 2.5 mol% isophthalic acid (IPA). The produced PET molten product was passed through a screen filter to remove impurities and produced a PET molten product with an intrinsic viscosity (IV) of 0.50 dl / g. (4) The molten PET material was fed into a meltblown spinning die and spun at a spinning temperature of 270°C. After solidification with high-pressure hot air at 270°C, meltblown fibers with an average diameter of 10 μm were produced. The produced fibers were then laminated to produce a meltblown nonwoven fabric, which is a self-bonding nonwoven fabric with a basis weight of 800 gsm.

[0051] Example 7: Production of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 6. However, unlike in Example 6, when the PET flake powder was crystallized in step (2), it was heated to a temperature of 90°C to ultimately produce the meltblown nonwoven fabric.

[0052] Example 8: Production of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 6. However, unlike in Example 6, when the PET flake powder was crystallized in step (2), it was heated to a temperature of 190°C to ultimately produce the meltblown nonwoven fabric.

[0053] Example 9: Production of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 6. However, unlike in Example 6, when manufacturing meltblown fibers in step (4), meltblown fibers with an average diameter of 1 μm were manufactured, and a meltblown nonwoven fabric was ultimately produced.

[0054] Example 10: Production of meltblown nonwoven fabric A meltblown nonwoven fabric was manufactured using the same method as in Example 6. However, unlike in Example 6, when manufacturing meltblown fibers in step (4), meltblown fibers with an average diameter of 25 μm were manufactured, and a meltblown nonwoven fabric was ultimately produced.

[0055] Experimental Example 1: Measurement of the physical properties of meltblown nonwoven fabric The experiments described below were performed on each of the meltblown nonwoven fabrics produced in Examples 1 to 10, and the results obtained are shown in Tables 1 and 2 below. (1) Rigidity The stiffness of the meltblown nonwoven fabrics produced in Examples 1 to 10 was measured using the analytical method specified in KS M 6518. (2) Sound absorption Using ALPHA CABIN equipment and in accordance with ISO 354 (Acoustics - Measurement of sound absorption in a reverberation room), the sound absorption coefficients of the meltblown nonwoven fabrics manufactured in Examples 1 and 2 were measured at 1000 Hz, 2000 Hz, 3150 Hz, and 5000 Hz, respectively (however, the sound absorption experiments were conducted using 840 mm x 840 mm flat test specimens without a frame, and the arithmetic mean was expressed after measuring five or more test specimens). (3) Compression modulus Each of the meltblown nonwoven fabrics produced in Examples 1 to 10 was cut to 100 mm x 100 mm to produce test pieces. These test pieces were placed between 100 x 100 x 0.8 mm steel plates, and a 500 g weight was placed in the center of the upper steel plate. The specimen was left to stand under the following conditions, the weights were removed, and the specimen was conditioned (conditions: left to stand for 1 hour at 23±2℃ and 50±5%RH). After conditioning, the compressive modulus was measured. (However, for thickness measurement, a 100x100mm specimen was placed on a specimen holder, a 120x120mm 150g pressure plate was placed on top of the specimen, and after compression, the thickness was measured at a pressure of 0.1kPa or less using a 1 square centimeter disc-shaped pressure device after 10 seconds. The thickness was measured at the midpoint of each side of the pressure plate, and the arithmetic mean of the four points was taken as the thickness. The measuring instrument used conformed to ISO 5084.)

[0056] <Condition> [1] Heat resistance: 120±2℃ x 1 hour → Thickness measured after being left at 23±2℃ and 50±5%RH for 1 hour. [2] Humidity resistance: Thickness was measured after being left at 40±2℃, 95%RH for 22 hours, then at 23±2℃ and 50±5%RH for 1 hour. [3] Compression modulus (%) = H1 / H0 x 100 (H0: thickness of the specimen before pressurization, H1: thickness of the specimen after pressurization aging)

[0057] [Table 1]

[0058] [Table 2]

[0059] As is clear from Table 1 above, it was confirmed that the meltblown nonwoven fabric produced in Example 2 had lower rigidity compared to the meltblown nonwoven fabric produced in Example 1. Furthermore, as is clear from Table 1 above, it was confirmed that the meltblown nonwoven fabric produced in Example 3 had lower rigidity compared to the meltblown nonwoven fabric produced in Example 1. Furthermore, as is clear from Table 1 above, it was confirmed that the meltblown nonwoven fabric produced in Example 4 had lower rigidity and low-frequency sound absorption coefficient compared to the meltblown nonwoven fabric produced in Example 1. Furthermore, as is clear from Table 1 above, it was confirmed that the meltblown nonwoven fabric produced in Example 5 had a lower high-frequency sound absorption coefficient compared to the meltblown nonwoven fabric produced in Example 1.

[0060] As is clear from Table 2 above, it was confirmed that the meltblown nonwoven fabric produced in Example 7 had lower rigidity compared to the meltblown nonwoven fabric produced in Example 6. Furthermore, as is clear from Table 2 above, it was confirmed that the meltblown nonwoven fabric produced in Example 8 had lower rigidity compared to the meltblown nonwoven fabric produced in Example 6. Furthermore, as is clear from Table 2 above, it was confirmed that the meltblown nonwoven fabric produced in Example 9 had lower rigidity compared to the meltblown nonwoven fabric produced in Example 6. Furthermore, as is clear from Table 2 above, it was confirmed that the meltblown nonwoven fabric produced in Example 10 had a lower high-frequency sound absorption coefficient compared to the meltblown nonwoven fabric produced in Example 6.

[0061] Although one embodiment of the present invention has been described above, the concept of the present invention is not limited to the embodiments presented herein. Those skilled in the art who understand the concept of the present invention can easily propose other embodiments within the same concept by adding, changing, deleting, or adding components, and these can also be said to fall within the scope of the present invention. [Industrial applicability]

[0062] The present invention relates to a meltblown nonwoven fabric, a multilayer spunbond nonwoven fabric containing the same, and a method for producing the same. The meltblown nonwoven fabric, which uses recycled polyester flakes and is environmentally friendly, also has excellent rigidity, sound absorption, and compressive modulus, making it suitable for use as a sound-absorbing material in automobiles. The meltblown nonwoven fabric, a multilayer spunbond nonwoven fabric containing the same, and a method for producing the same are suitable for use in automotive internal materials such as wheel guards and trunk trims where rigidity, sound absorption, and compressive modulus are required.

Claims

1. A first step of crushing recycled polyester flakes to produce polyester flake powder; The second step involves heating the polyester flake powder at a temperature of 100-180°C to crystallize it; The third step involves melting crystallized polyester flake powder to produce a molten product; The process includes a fourth step of spinning a molten material to produce meltblown fibers, and laminating the produced fibers to produce a meltblown nonwoven fabric having a basis weight of 100 to 900 gsm; A method for producing a meltblown nonwoven fabric, characterized in that the molten material contains 0.3 to 3.0 mol% isophthalic acid (IPA).

2. The method for producing a meltblown nonwoven fabric according to claim 1, characterized in that the recycled polyester flakes include one or more selected from polyethylene terephthalate (PET) flakes, polytetramethylene terephthalate (PTT) flakes, and polybutylene terephthalate (PBT) flakes.

3. The method for producing a meltblown nonwoven fabric according to claim 1, characterized in that the flake powder produced in the first step has an average particle size of 1 to 10 mm.

4. The method for producing a meltblown nonwoven fabric according to claim 1, characterized in that the molten material produced in the third step has an intrinsic viscosity (IV) of 0.40 to 0.60 dl / g.

5. The method for producing a meltblown nonwoven fabric according to claim 1, characterized in that the meltblown fibers produced in the fourth step have an average diameter of 0.5 to 20 μm.

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