A high-comfort one-way moisture-conducting nonwoven fabric and preparation method thereof

Abstract

The present invention discloses a highly comfortable unidirectional moisture-conducting nonwoven fabric and a preparation method thereof, and belongs to the technical field of nonwoven fabrics. The nonwoven fabric comprises a concave-convex cotton mesh layer and a PLA fiber mesh, wherein the concave-convex cotton mesh layer is a cotton mesh with a concave-convex structure obtained by alkali shrinkage treatment of the cotton mesh, and the PLA fiber mesh is prepared from PLA masterbatch as a raw material, and the concave-convex cotton mesh layer and the PLA fiber mesh are compounded and reinforced by spunlace. The nonwoven fabric prepared by the present invention has a unidirectional moisture-conducting function, and a concave-convex structure is formed on the side in contact with the human body, thereby increasing comfort; while the alkali shrinkage treatment forms the concave-convex structure, the cotton mesh is partially degreased, thereby ensuring a certain water absorption and making the fiber soft and shiny; in addition, polylactic acid fiber has excellent biocompatibility and antibacterial properties, and the compounding with cotton fiber makes up for the defect that cotton fiber absorbs moisture and easily breeds bacteria.

Description

Technical Field

[0001] The invention belongs to the technical field of nonwoven fabrics, and particularly relates to a highly comfortable unidirectional moisture-conducting nonwoven fabric and a preparation method thereof. Background Art

[0002] Today's society is constantly progressing, science and technology are advancing by leaps and bounds, and various new materials and new processes are constantly being applied to the textile industry. However, no matter how new materials, new processes and new functions change, consumers' demand for pure cotton products is still the first choice, and at the same time, they have also put forward higher requirements for pure cotton cloth. The texture of natural fiber is comfortable and skin-friendly. Giving it more functions on this basis has become a consumer trend and market pursuit. The requirements for natural fiber comfort and skin-friendliness are very high, especially for infant and maternal products, which put forward higher requirements for pure cotton comfortable and skin-friendly functional fabrics. Among the many types of fabrics, unidirectional moisture-conducting fabrics use unidirectional moisture-conducting design to enable sweat or water to diffuse quickly from one side of the fabric to the other side, which meets people's pursuit of a comfortable and healthy life.

[0003] The prior art provides a variety of one-way moisture-conducting treatment solutions, as follows:

[0004] For example, the patent with application number CN200910239652.X discloses a one-way moisture-conducting all-cotton spunlace nonwoven fabric, product and manufacturing method thereof, wherein the all-cotton spunlace nonwoven fabric comprises an all-cotton spunlace nonwoven fabric substrate, wherein the all-cotton spunlace nonwoven fabric substrate comprises a hydrophobic surface and a hydrophilic surface, wherein the hydrophobic surface contains a hydrophobic substance for conducting moisture from the hydrophobic surface to the hydrophilic surface.

[0005] For example, the patent with application number CN201710206970.0 discloses a preparation process of pure cotton unidirectional moisture-conducting non-woven fabric, including: overlapping, a hydrophilic cotton web and a water-repellent mesh all-cotton spunlace non-woven fabric are overlapped with each other to form a composite cotton web; spunlace compounding, the composite cotton web is spunlace reinforced by a spunlace device, and the hydrophilic cotton web fibers and the mesh spunlace non-woven fabric are entangled and embraced with each other through the action of high-pressure water needles, and the two are combined into one; drying into rolls, the spunlace compounded all-cotton non-woven fabric is dried and rolled.

[0006] For example, the patent with application number CN201910810237.9 discloses a method for preparing a unidirectional moisture-conducting antibacterial non-woven fabric, which includes the following steps:

[0007] S1, opening and forming a web: respectively feeding kapok fibers with a length of 15-5 mm and hydrophilic cotton fibers with a length of 25-45 mm into an opening machine to form a web;

[0008] S2, pre-punching: pre-punching the kapok fiber web and the hydrophilic cotton fiber web after opening into a web by needle punching to obtain a kapok fiber web layer and a cotton fiber web layer;

[0009] S3, composite forming: laying the pre-punctured cotton fiber mesh layer on the kapok fiber mesh layer, and then composite forming the fiber felt by needle punching;

[0010] S4, modification of composite fiber web layer: using antibacterial hydrophilic finishing agent to impregnate the composite fiber felt;

[0011] S5, curing: drying the modified semi-finished product until the moisture content is less than 3%;

[0012] S6, finished product coiling or product.

[0013] For example, the patent with application number CN 202110366242.2 discloses a unidirectional moisture-conducting material, including a base layer, one surface of the base layer is provided with a hydrophilic fiber membrane, and the other surface of the base layer is infiltrated with a hydrophobic polymer; the average pore size of the base layer is larger than the average pore size of the hydrophilic fiber membrane.

[0014] For example, the patent application number CN201410190317.6 discloses a spunlace nonwoven material with a one-way water-conducting function, wherein the spunlace nonwoven material is made by combing hydrophilic fibers and hydrophobic fibers into a web and then compounding and spunlace reinforcement; wherein the surface density of the hydrophilic fiber web is 30-60 g / m 2 The surface density of the hydrophobic fiber web is 30-60g / m 2 .

[0015] From the above patents, it can be seen that there are generally two methods for unidirectional moisture conduction: one is to make the inner surface hydrophobic or the outer surface hydrophilic by hydrophilic finishing or hydrophobic finishing or modification, printing and other methods, increase the capillary force difference between the inner and outer surfaces, so as to achieve the effect of unidirectional moisture conduction and moisture absorption and quick drying, but this type of fabric is lacking in moisture permeability and breathability, and the stability of chemical finishing agents is not high, which affects the durability of the fabric. The other is to weave by selecting raw materials with different hygroscopicity and hygroscopicity, with water-repellent fibers as the inner surface and hydrophilic fibers as the outer surface; the raw materials with different hygroscopicity and hygroscopicity are different materials, fibers of different thicknesses and different gram weights, etc. The above methods have poor unidirectional moisture conduction effects, and are usually combined with hydrophilic treatment and hydrophobic treatment, such as CN201710206970.0, CN201910810237.9, CN202110366242.2, CN201410190317.6, etc. In short, to achieve a good one-way moisture conduction effect, both hydrophilic treatment and hydrophobic treatment are required, and corresponding reagents must be used, which may involve problems such as residue, durability, stability, production cost, and the use of chemical agents. In addition, the hydrophobic side is in contact with the human body. The hydrophobic treatment is not dehydrated or treated with a hydrophobic agent, which will retain a colloid layer or form a hydrophobic layer on the fiber surface, making the fiber harder and less comfortable. Summary of the invention

[0016] In order to solve the above problems, the present invention provides a highly comfortable unidirectional moisture-conducting nonwoven fabric and a preparation method thereof, which has a unidirectional moisture-conducting function and forms a concave-convex structure on the side in contact with the human body to increase comfort; the alkali shrinkage treatment will partially degrease the cotton mesh while forming the concave-convex structure, making the fiber soft and shiny while ensuring a certain water absorption; in addition, polylactic acid fiber has excellent biocompatibility and antibacterial properties, and the composite with cotton fiber makes up for the defect that cotton fiber is easy to breed bacteria due to moisture absorption. The technical scheme is as follows:

[0017] On the one hand, the present invention provides a highly comfortable unidirectional moisture-conducting nonwoven fabric, comprising a concave-convex cotton mesh layer and a PLA fiber mesh. The concave-convex cotton mesh layer is a cotton mesh with a concave-convex structure obtained by alkali shrinkage treatment of the cotton mesh, the PLA fiber mesh is prepared from PLA masterbatch as a raw material, and the concave-convex cotton mesh layer and the PLA fiber mesh are compounded and reinforced by hydroentanglement. The diameter of the fiber of the PLA fiber mesh is much smaller than that of the cotton fiber, and after being made into a fiber mesh, the mesh aperture is also much smaller than that of the cotton mesh.

[0018] The weight of the PLA fiber mesh in the present invention is 20-80 g / m 2 The weight of the concave-convex cotton mesh layer is 20-80g / m 2 .

[0019] On the other hand, the present invention also provides a method for preparing the aforementioned high-comfort unidirectional moisture-conducting nonwoven fabric, comprising the following steps:

[0020] (1) Preparation of PLA fiber web: PLA fiber web was prepared using PLA masterbatch as raw material.

[0021] (2) Preparation of the concave-convex cotton mesh layer: The cotton mesh is subjected to alkali shrinkage and water washing to obtain the concave-convex cotton mesh layer. Cotton fibers will shrink longitudinally in the caustic soda solution to form a fine concave-convex structure, which reduces the contact area with the skin and increases the comfort of the nonwoven fabric.

[0022] (3) Spunlace: PLA fiber web and concave-convex cotton web layer are compounded and reinforced by spunlace to obtain nonwoven fabric. Among them, the spunlace treatment can further wash the concave-convex cotton web layer to reduce the possibility of residue.

[0023] (4) Drying: Drying the nonwoven fabric to obtain the product.

[0024] Wherein, in step (1), the preparation process of the PLA fiber web is as follows: the polylactic acid masterbatch is dried, melted, extruded, melt-blown and air-drawn to obtain the PLA fiber web on a laid mesh curtain.

[0025] The drying process of the polylactic acid masterbatch is: drying in a vacuum oven at 75-85°C for 7-10 hours; the extrusion process is: extrusion temperature is 180-190°C, screw speed is 50-60r / min, and winding speed is 50-60m / min.

[0026] The alkali shrinkage treatment process is: immersing in 8-10wt% caustic soda solution at room temperature for 10-15 minutes.

[0027] The beneficial effects brought by the technical solution provided by the present invention are:

[0028] (1) The raw materials used in the present invention are PLA fiber and cotton fiber, both of which are degradable fibers.

[0029] (2) PLA fiber is an ultrafine fiber. When combined with cotton fiber, it can create pore differences in thickness, form a differential capillary effect, and achieve rapid unidirectional moisture conduction.

[0030] (3) Cotton nonwoven fabric has a fine concave-convex structure, which reduces the contact area between the nonwoven fabric and the skin and increases the comfort of the nonwoven fabric.

[0031] (4) Polylactic acid fiber has excellent biocompatibility and antibacterial properties. Its combination with cotton fiber makes up for the defect that cotton fiber is hygroscopic and easy to breed bacteria.

[0032] (5) Alkali shrinkage partially degreases the cotton fibers, making the product soft and shiny. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in further detail below.

[0034] Embodiment 1:

[0035] Embodiment 1 provides a method for preparing a highly comfortable unidirectional moisture-conducting nonwoven fabric, the method comprising:

[0036] (1) Preparation of PLA fiber web: PLA masterbatch was used as raw material to prepare a fiber web with a gram weight of 60 g / m 2 PLA fiber mesh.

[0037] (2) Preparation of the concave-convex cotton mesh layer: The cotton fibers are opened, combed and laid to obtain a 60 g / m 2 The cotton fiber web is then immersed in a 10wt% caustic soda solution at room temperature for 10 minutes for alkali shrinkage and water washing to obtain a concave-convex cotton web layer.

[0038] (3) Hydroentanglement: The PLA fiber web and the concave-convex cotton web layer are compounded and reinforced by hydroentanglement to obtain a nonwoven fabric.

[0039] (4) Drying: Drying the nonwoven fabric to obtain the product.

[0040] Comparative Example 1:

[0041] Comparative Example 1 provides a method for preparing a nonwoven fabric, and its process is basically the same as that of Example 1, except that: step (1) in this example uses raw cotton fiber as raw material.

[0042] Comparative Example 2:

[0043] Comparative Example 2 provides a method for preparing a common spunlace nonwoven fabric, wherein the raw material is raw cotton fiber with a gram weight of 120 g / m 2 .

[0044] Verification Example

[0045] The liquid penetration performance and wetting radius test were conducted on Example 1 and Comparative Examples 1-2. The liquid longitudinal diffusion performance test was conducted in accordance with the standard GB / T 24218.13-2010 "Test methods for textile nonwoven fabrics Part 13: Determination of multiple liquid penetration time", and the test was conducted using a YG814D liquid penetration meter. The wetting radius test was conducted in accordance with the standard ASTMD1776. The sample was humidified at a temperature of 21°C and a relative humidity of RH65% for 24 hours before being tested. The test performance is shown in Table 1:

[0046] Table 1

[0047]

[0048] It can be seen from Table 1 that Example 1 is a nonwoven fabric composed of a PLA fiber layer and a cotton fiber layer. When liquid is dropped on the front of the nonwoven fabric, the lateral diffusion radius is only 0.6 cm, and the liquid can be quickly diverted to the other side. On the contrary, when the liquid is on the back, the liquid quickly diffuses laterally and will not be diverted longitudinally to the other side, indicating that it has excellent unidirectional moisture conduction performance and good anti-reverse osmosis effect. In Comparative Example 1, PLA fiber is replaced with cotton fiber. Although it has been alkali-shrinked, the pore size difference between its fiber layers is not obvious, so it basically does not have unidirectional moisture conduction performance, but it still has a certain contribution to unidirectional moisture conduction, that is, the concave-convex structure makes the product more comfortable while further improving the unidirectional moisture conduction performance. Comparative Example 2 is an ordinary cotton nonwoven fabric, which relies on its own hygroscopicity to absorb liquid and does not have the effect of unidirectional moisture conduction. It can also be seen from the wetting radius that the nonwoven fabric in Example 1 has better unidirectional moisture conduction performance than the nonwoven fabrics in other cases.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly comfortable one-way moisture-conducting nonwoven fabric, characterized in that: It comprises a concave-convex cotton mesh layer and a PLA fiber mesh, wherein the concave-convex cotton mesh layer is a cotton mesh with a concave-convex structure obtained by alkali shrinkage treatment of the cotton mesh, the PLA fiber mesh is prepared from PLA masterbatch as a raw material, and the concave-convex cotton mesh layer and the PLA fiber mesh are compounded and reinforced by hydroentanglement; The method comprises the following steps: (1) Preparation of PLA fiber web: PLA fiber web was prepared using PLA masterbatch as raw material; (2) Preparation of the concave-convex cotton mesh layer: subjecting the cotton mesh to alkali shrinkage and water washing treatment to obtain the concave-convex cotton mesh layer; (3) Spunlace: The PLA fiber web and the concave-convex cotton web layer are compounded and reinforced by spunlace to obtain a nonwoven fabric; (4) Drying: Drying the nonwoven fabric to obtain the product; In step (1), the preparation process of the PLA fiber web is as follows: the polylactic acid masterbatch is dried, melted, extruded, melt-blown and air-drawn to obtain the PLA fiber web on a laid net curtain; The process of alkali shrinkage treatment is: immerse in 8-10wt% caustic soda solution at room temperature for 10-15 minutes.

2. The high-comfort one-way moisture-conducting nonwoven fabric according to claim 1, characterized in that: The weight of the PLA fiber web is 20-80 g / m 2 .

3. The high-comfort one-way moisture-conducting nonwoven fabric according to claim 1, characterized in that: The gram weight of the concave-convex cotton mesh layer is 20-80g / m 2 .

4. The high-comfort one-way moisture-conducting nonwoven fabric according to claim 1, characterized in that: The drying process of the polylactic acid masterbatch is: drying in a vacuum oven at 75-85°C for 7-10 hours; the extrusion process is: the extrusion temperature is 180-190°C, the screw speed is 50-60r / min, and the winding speed is 50-60m / min.

Images