Preparation process of high-loft strong and tough double-spun material based on three-dimensional fiber network construction

Abstract

The application discloses a kind of based on the preparation process of high fluffy strong tough double-spun material of fiber three-dimensional network construction, comprising the following steps: the forming of first mixed fiber web, the forming of reinforcing web, the forming of second mixed fiber web, fluffy processing and cooling setting, fiber three-dimensional network structure is sent into oven, hot air is blown from the path of fiber three-dimensional network structure direction down, so that low melting point fiber carries out hot melt, realizes the fixation to surrounding superfine melt-blown fiber or wood pulp fiber, and utilize the first negative pressure box of being arranged in the path below fiber three-dimensional network structure and take away broken superfine melt-blown fiber, wood pulp fiber and low melting point fiber on the excess hot melt part, realize fluffy processing, obtain semi-finished product, utilize low melting point fiber to strengthen structure, enhance the toughness of double-spun material, need not heat pressing roller to be set and be treated, ensure the high fluffy effect of double-spun material.

Description

Technical Field

[0001] This invention relates to the field of double-spun material production technology, and in particular to a process for preparing high-loft, high-strength double-spun materials based on a three-dimensional fiber network. Background Technology

[0002] The production of double-spun materials (twin-spun nonwoven materials) is usually achieved by using meltblown microfiber and wood pulp fiber as raw materials and producing them through a dry process.

[0003] Because double-spun materials contain some wood pulp fibers, and these fibers are typically short, they have poor toughness and are prone to deformation or even breakage under tension or impact. To enhance toughness, hot-pressing rollers can be used for shaping; however, this process reduces the bulkiness of the material, affecting breathability and user experience, and therefore requires improvement. Summary of the Invention

[0004] The main technical problem solved by this invention is to provide a process for preparing high-loft and strong double-spun materials based on a three-dimensional fiber network, which enhances the toughness of the material and ensures a high-loft effect.

[0005] To solve the above-mentioned technical problems, one technical solution adopted by the present invention is: to provide a process for preparing a high-loft, high-strength double-spun material based on a three-dimensional fiber network, comprising the following steps: S1. Forming of the first mixed fiber web: The meltblown fiber raw material is fed into a screw extruder, and after the melt is extruded, it is fed into a metering pump. The metering pump is used to send the melt into the first spinneret to spray out ultrafine meltblown fibers with a diameter of 2 to 4 micrometers. After the wood pulp fibers are combed into single fibers, compressed air is used to send the wood pulp fibers to the first airflow web forming nozzle for spraying. The low-melting-point fibers are combed into single fibers and then sent to the second airflow web forming nozzle for ejection using compressed air. Ultrafine meltblown fibers are mixed with sprayed wood pulp fibers and low-melting-point fibers in an airflow field and laid on the condensing screen of the web forming machine to form the first mixed fiber web; S2. Forming of the reinforcing mesh: The meltblown fiber raw material is fed into a screw extruder, and after the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the second spinneret to spray out ultrafine meltblown fibers with a diameter of 2 to 4 micrometers. The low-melting-point fibers are combed into single fibers and then sent to the third airflow web forming nozzle for ejection using compressed air. Ultrafine meltblown fibers are mixed with sprayed low-melting-point fibers in an airflow field and then laid on a first mixed fiber web to form a reinforcing web. S3, Forming of the second mixed fiber web: The meltblown fiber raw material is fed into a screw extruder, and after the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the third spinneret to spray out ultrafine meltblown fibers with a diameter of 2 to 4 micrometers. After the wood pulp fibers are combed into single fibers, compressed air is used to send the wood pulp fibers to the fourth airflow web forming nozzle for spraying. The low-melting-point fibers are combed into single fibers and then sent to the fifth airflow web forming nozzle for ejection using compressed air. Ultrafine meltblown fibers are mixed with sprayed wood pulp fibers and low-melting-point fibers in an airflow field and then laid on a reinforcing mesh to form a second mixed fiber mesh, resulting in a three-layer composite fiber three-dimensional network structure. S4. Fluffing treatment: The three-dimensional fiber network structure is sent into the oven, and hot air is blown downward from above the path of the three-dimensional fiber network structure to heat melt the low-melting-point fibers, thereby achieving adhesion to the surrounding ultrafine meltblown fibers or wood pulp fibers. The first negative pressure box set below the path of the three-dimensional fiber network structure is used to remove the broken ultrafine meltblown fibers, wood pulp fibers and excess heat-melted parts on the low-melting fibers, achieving fluffing treatment and obtaining a semi-finished product. S5, Cooling and Shaping: After the semi-finished product is output from the oven, it enters the shaping chamber. Cold air is blown upward from below the semi-finished product path to cool it. The remaining broken ultrafine meltblown fibers and wood pulp fibers are carried away by the second negative pressure box set above the fiber three-dimensional network structure path.

[0006] In the first mixed fiber web, the proportions of ultrafine meltblown fiber, wood pulp fiber and low melting point fiber are (50~70):(30~50):(2~4).

[0007] In the second mixed fiber web, the proportions of ultrafine meltblown fiber, wood pulp fiber and low melting point fiber are (50~70):(30~50):(2~4).

[0008] In the reinforcing mesh, the ratio of ultrafine meltblown fiber to low-melting-point fiber is (80~100):(2~4).

[0009] The wood pulp fibers are 3-5 mm in length.

[0010] The low-melting-point fiber is ES fiber, which includes a polypropylene core layer and a polyethylene sheath layer, with the polyethylene sheath layer wrapping around the outside of the polypropylene core layer.

[0011] The length of the low-melting-point fiber is 5~10mm.

[0012] The temperature of the hot air in the oven is 120~130℃.

[0013] The meltblown fiber raw material is PP or PLA.

[0014] The beneficial effects of this invention are: the invention provides a high-loft and strong double-spun material preparation process based on a three-dimensional fiber network, which features a specially designed reinforcing mesh and utilizes low-melting-point fibers for three-dimensional structural reinforcement, thereby enhancing the toughness of the double-spun material. Moreover, it eliminates the need for hot press rollers for shaping, ensuring the high loft effect and good air permeability of the double-spun material. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of the structure of the high-loft, high-strength double-spun material prepared by the present invention. Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Please see Figure 1 The embodiments of the present invention include: A process for preparing a high-loft, high-strength double-spun material based on a three-dimensional fiber network includes the following steps: S1. Forming of the first mixed fiber web 1: 50-70 parts by weight of meltblown fiber raw material are fed into a screw extruder. After the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the first spinneret to extrude ultrafine meltblown fibers with a diameter of 2-4 micrometers. In this embodiment, the meltblown fiber raw material is PP or PLA. PP ultrafine meltblown fibers have good toughness, while PLA ultrafine meltblown fibers have good environmental performance, wide applicability, and flexible selection. 30-50 parts by weight of wood pulp fibers are combed into single fibers and then sent to the first airflow web forming nozzle for spraying using compressed air. In this embodiment, the length of the wood pulp fibers is 3-5 mm. The wood pulp fibers are relatively short, but have good water absorption. Two to four parts by weight of low-melting-point fibers are combed into single fibers and then sent to a second airflow web forming nozzle for ejection using compressed air. In this embodiment, the length of the low-melting-point fibers is 5 to 10 mm, which is a moderate length. Specifically, the low-melting-point fibers are ES fibers, which include a polypropylene core layer and a polyethylene sheath. The polyethylene sheath wraps around the polypropylene core layer, maintaining the properties of the fiber body through the polypropylene core layer and achieving subsequent hot melt bonding through the polyethylene sheath. Ultrafine meltblown fibers are mixed with sprayed wood pulp fibers and low-melting-point fibers in an airflow field and laid on the condensing screen of the web forming machine to form the first mixed fiber web 1; In this embodiment, the proportions of ultrafine meltblown fiber, wood pulp fiber, and low-melting-point fiber in the first mixed fiber web 1 are (50~70):(30~50):(2~4); S2, Forming of reinforcing mesh 3: 80-100 parts by weight of meltblown fiber raw material are fed into a screw extruder. After the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the second spinneret to spray out ultrafine meltblown fibers with a diameter of 2-4 micrometers. Two to four parts by weight of low-melting-point fibers are combed into single fibers and then compressed air is used to send the low-melting-point fibers to the third airflow web forming nozzle for ejection. Ultrafine meltblown fibers and sprayed low-melting-point fibers are mixed in an airflow field and laid on the first mixed fiber web 1 to form a reinforcing web 3. In this embodiment, the reinforcing web 3 is mainly made of meltblown fibers and does not contain wood pulp fibers, which improves the structural toughness. S3, Forming of the second mixed fiber web 2: 50-70 parts by weight of meltblown fiber raw material are fed into a screw extruder. After the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the third spinneret to extrude ultrafine meltblown fibers with a diameter of 2-4 micrometers. 30-50 parts by weight of wood pulp fibers are combed into single fibers and then compressed air is used to send the wood pulp fibers to the fourth airflow web forming nozzle for spraying. Two to four parts by weight of low-melting-point fibers are combed into single-fiber state and then sent to the fifth airflow web forming nozzle for ejection using compressed air. The ultrafine meltblown fibers are mixed with the sprayed wood pulp fibers and low melting point fibers in the airflow field and laid on the reinforcing mesh 3 to form the second mixed fiber mesh 2, resulting in a three-layer composite fiber three-dimensional network structure as shown in Figure 1. S4. Fluffing treatment: The three-dimensional fiber network structure is fed into an oven, and hot air is blown downwards from above the path of the three-dimensional fiber network structure, causing the polyethylene skin on the surface of the low melting point fiber to melt and achieve adhesion to the surrounding ultrafine meltblown fiber or wood pulp fiber. In the oven, the temperature of the hot air is 120~130℃, which can ensure the melting of the polyethylene skin and avoid damage to the polypropylene core layer, thus ensuring the toughness, tensile strength and impact resistance of the structure. The first negative pressure box, located below the fiber three-dimensional network structure path, removes the excess hot melt portion from the broken ultrafine meltblown fibers, wood pulp fibers, and low melting point fibers, achieving a fluffing process and obtaining a semi-finished product. This eliminates the need for hot press rollers for shaping, ensuring the high fluffiness of the double-spun material and thus improving its breathability. S5, Cooling and Shaping: After the semi-finished product is output from the oven, it enters the shaping chamber. Cold air is blown upward from below the semi-finished product path to cool it down. The remaining broken ultrafine meltblown fibers and wood pulp fibers are carried away by the second negative pressure box set above the fiber three-dimensional network structure path, increasing the voids in the fiber three-dimensional network structure and further ensuring the fluffy effect.

[0018] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A process for preparing a high-loft, high-strength double-spun material based on a three-dimensional fiber network, characterized in that, Includes the following steps: S1. Forming of the first mixed fiber web: The meltblown fiber raw material is fed into a screw extruder, and after the melt is extruded, it is fed into a metering pump. The metering pump is used to send the melt into the first spinneret to spray out ultrafine meltblown fibers with a diameter of 2 to 4 micrometers. After the wood pulp fibers are combed into single fibers, compressed air is used to send the wood pulp fibers to the first airflow web forming nozzle for spraying. The low-melting-point fibers are combed into single fibers and then sent to the second airflow web forming nozzle for ejection using compressed air. Ultrafine meltblown fibers are mixed with sprayed wood pulp fibers and low-melting-point fibers in an airflow field and laid on the condensing screen of the web forming machine to form the first mixed fiber web; S2. Forming of the reinforcing mesh: The meltblown fiber raw material is fed into a screw extruder, and after the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the second spinneret to spray out ultrafine meltblown fibers with a diameter of 2 to 4 micrometers. The low-melting-point fibers are combed into single fibers and then sent to the third airflow web forming nozzle for ejection using compressed air. Ultrafine meltblown fibers are mixed with sprayed low-melting-point fibers in an airflow field and then laid on a first mixed fiber web to form a reinforcing web. S3, Forming of the second mixed fiber web: The meltblown fiber raw material is fed into a screw extruder, and after the melt is extruded, it is fed into a metering pump. The metering pump is used to feed the melt into the third spinneret to spray out ultrafine meltblown fibers with a diameter of 2 to 4 micrometers. After the wood pulp fibers are combed into single fibers, compressed air is used to send the wood pulp fibers to the fourth airflow web forming nozzle for spraying. The low-melting-point fibers are combed into single fibers and then sent to the fifth airflow web forming nozzle for ejection using compressed air. Ultrafine meltblown fibers are mixed with sprayed wood pulp fibers and low-melting-point fibers in an airflow field and then laid on a reinforcing mesh to form a second mixed fiber mesh, resulting in a three-layer composite fiber three-dimensional network structure. S4. Fluffing treatment: The three-dimensional fiber network structure is sent into the oven, and hot air is blown downward from above the path of the three-dimensional fiber network structure to heat melt the low-melting-point fibers, thereby achieving adhesion to the surrounding ultrafine meltblown fibers or wood pulp fibers. The first negative pressure box set below the path of the three-dimensional fiber network structure is used to remove the broken ultrafine meltblown fibers, wood pulp fibers and excess heat-melted parts on the low-melting fibers, achieving fluffing treatment and obtaining a semi-finished product. S5, Cooling and Shaping: After the semi-finished product is output from the oven, it enters the shaping chamber. Cold air is blown upward from below the semi-finished product path to cool it. The remaining broken ultrafine meltblown fibers and wood pulp fibers are carried away by the second negative pressure box set above the fiber three-dimensional network structure path.

2. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, In the first mixed fiber web, the proportions of ultrafine meltblown fiber, wood pulp fiber and low melting point fiber are (50~70):(30~50):(2~4).

3. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, In the second mixed fiber web, the proportions of ultrafine meltblown fiber, wood pulp fiber and low melting point fiber are (50~70):(30~50):(2~4).

4. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, In the reinforcing mesh, the ratio of ultrafine meltblown fiber to low-melting-point fiber is (80~100):(2~4).

5. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, The length of the wood pulp fibers is 3~5mm.

6. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, The low-melting-point fiber is ES fiber, which includes a polypropylene core layer and a polyethylene sheath layer, with the polyethylene sheath layer wrapping around the outside of the polypropylene core layer.

7. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, The length of the low-melting-point fiber is 5~10mm.

8. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, The temperature of the hot air in the oven is 120~130℃.

9. The preparation process of high-loft, high-strength double-spun material based on a three-dimensional fiber network according to claim 1, characterized in that, The meltblown fiber raw material is PP or PLA.

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