A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for use in the hygiene field

Abstract

A method for preparing a comfortable, unidirectional moisture-wicking nonwoven fabric for the hygiene field involves first preparing a mixed fiber web from viscose and cotton fibers. Then, the mixed fiber web is sequentially subjected to forward hydroentangling, reverse hydroentangling, and forward hydroentangling again to obtain a post-hydroentangled fiber web. During forward hydroentangling, the viscose fibers are carried downwards by the hydronephrite jets. During reverse hydroentangling, some viscose fibers are carried upwards by the hydronephrite jets. The hydroentangling pressure is greater in forward hydroentangling than in reverse hydroentangling. In the post-hydroentangled fiber web, the viscose fiber content increases from top to bottom. Finally, the post-hydroentangled fiber web is dried to obtain a comfortable and fast unidirectional moisture-wicking hydroentangled nonwoven fabric. This design not only enables the blending of cotton and viscose fibers to produce unidirectional moisture-wicking cotton-containing hydroentangled nonwoven fabrics but also offers strong environmental friendliness, low backflow, and high comfort.

Description

Technical Field

[0001] This invention relates to a unidirectional moisture-wicking nonwoven fabric for use in the hygiene field, belonging to the field of nonwoven fabrics, and particularly to a method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for use in the hygiene field. Background Technology

[0002] Currently, viscose fiber has good moisture absorption, with a moisture regain of around 13% under normal atmospheric conditions. Because viscose fiber expands significantly after absorbing moisture, increasing in diameter by up to 50%, viscose products feel stiff and are less comfortable after washing. In contrast, cotton fiber has excellent skin-friendly and comfortable properties. Therefore, blending cotton and viscose fibers would significantly reduce the stiffness of viscose products after absorbing moisture and improve comfort. However, due to the performance differences between viscose and cotton fibers, they cannot be simultaneously blended and carded into single fibers.

[0003] Natural fibers are comfortable and skin-friendly, and adding more functions on this basis has become a consumer trend and market pursuit. With the improvement of living standards, people have higher and higher requirements for the comfort and skin-friendliness of natural fibers, especially for infant and child products. Higher requirements are placed on pure cotton comfortable and skin-friendly functional fabrics. It is hoped that all-cotton spunlace nonwoven products used in hygiene materials can absorb moisture quickly and have low backflow. However, because all-cotton spunlace nonwoven fabrics cannot quickly wick away moisture after absorbing it, it will bring users discomfort such as damp cold, stickiness or stuffiness. In order to solve this defect, existing technologies mostly adopt finishing methods to achieve the one-way moisture wicking performance of all-cotton spunlace nonwoven fabrics. However, the chemical reagents used in finishing are not environmentally friendly.

[0004] The information disclosed in this background section is intended only to enhance understanding of the overall background of this application and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings and problems of existing technologies, such as the difficulty in uniformly blending cotton fibers and viscose fibers, and the lack of environmental friendliness of existing unidirectional moisture-wicking cotton spunlace nonwoven fabrics. This invention provides a method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the hygiene field that can uniformly blend cotton fibers and viscose fibers to produce unidirectional moisture-wicking cotton spunlace nonwoven fabrics and has strong environmental friendliness.

[0006] To achieve the above objectives, the technical solution of the present invention is: a method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field, the preparation method comprising the following steps:

[0007] Step 1: Mix viscose fiber and cotton fiber into a web to obtain a mixed fiber web. In this mixed fiber web, the weight of cotton fiber is greater than the weight of viscose fiber, and the initial modulus of viscose fiber is less than that of cotton fiber.

[0008] Step 2: First, hydroentangle the mixed fiber web from above in the forward direction. During the forward hydroentanglement, the viscose fibers are carried by the water jets and slide downwards. After the forward hydroentanglement is completed, hydroentangle the mixed fiber web from below in the reverse direction. Some viscose fibers are carried by the water jets and slide upwards. After the reverse hydroentanglement is completed, hydroentangle the mixed fiber web from above in the forward direction to obtain a barbed fiber web. The hydroentanglement pressure in the forward direction is greater than that in the reverse direction. In the barbed fiber web, the viscose fiber content shows a gradient distribution trend of gradually increasing from top to bottom.

[0009] Step 3: After drying the spunlace fiber web, a comfortable and fast-drying unidirectional moisture-wicking spunlace nonwoven fabric is obtained.

[0010] In the first step, the viscose fiber has a fineness of 0.5-1.2 dtex, and the cotton fiber has a fineness of 1.43-2.22 dtex.

[0011] The weight of the hybrid fiber web is 20-150 g / m².

[0012] In the mixed fiber web, the dry weight ratio of the viscose fiber and cotton fiber is 3-4:6-7.

[0013] In the first step, the process of mixing viscose fiber and cotton fiber to form a web to obtain a mixed fiber web refers to: firstly, opening and removing impurities from viscose fiber and cotton fiber separately and then mechanically combing them to obtain viscose fiber web and cotton fiber web, and then stacking the viscose fiber web and cotton fiber web layer by layer to obtain a superimposed web. The superimposed web contains at least one viscose fiber web and one cotton fiber web. Then, the superimposed web is fed into a carding machine through a cotton roller for mixing and carding to obtain a mixed fiber web.

[0014] The number of viscose fiber webs in the superimposed mesh is two layers, and the number of cotton fiber webs is three layers. The superimposition order of viscose fiber webs and cotton fiber webs is cotton fiber web, viscose fiber web, cotton fiber web, viscose fiber web, and cotton fiber web.

[0015] The dry weight ratios of the cotton fiber web, viscose fiber web, cotton fiber web, viscose fiber web, and cotton fiber web are: 20-25, 15-20, 10-30, 15-20, and 20-25.

[0016] After the second step is completed, the burred fiber web first undergoes a textured surface manufacturing step, and then proceeds to the third step; the textured surface manufacturing step refers to:

[0017] The punctured fiber web is passed around the outer side of the convex-concave roller, which includes a roller body and a plurality of protruding patterns thereon. There are pits between adjacent protruding patterns. During the process of passing around, the hydroentanglement head located next to the convex-concave roller 5 hydroentangles the punctured fiber web.

[0018] When the water jet passes through the post-spinning fiber web and impacts the convex-concave roller, if the water jet impacts the convex pattern, the fibers above the convex pattern will move towards the depressions and pits in the convex pattern, causing them to entangle with each other, thereby reducing the thickness of the post-spinning fiber web at that point. If the water jet impacts the pit, the water jet will penetrate directly, and the fibers above the pit will move downwards. At the same time, the fibers above the aforementioned convex pattern will move towards the pit, compressing and forming a region where longitudinal and transverse fibers gather. Finally, after the hydroentangling is completed, the post-spinning fiber web meshes with the convex-concave roller, forming a pattern on the post-spinning fiber web that corresponds to the convex pattern.

[0019] The shape of the raised pattern can be any one or any combination of circles, ovals, polygons, stars, animal patterns, and plant patterns.

[0020] A product of a method for preparing a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field, wherein the product is the result of the above-mentioned method for preparing a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field, namely, a comfortable and fast one-way moisture-wicking spunlace nonwoven fabric for the sanitary field.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. In the preparation method of a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to the present invention, viscose fiber and cotton fiber are first prepared into a mixed fiber web, and then the mixed fiber web is subjected to forward hydroentangling, reverse hydroentangling, and forward hydroentangling in sequence to obtain a post-hydroentangled fiber web. The post-hydroentangled fiber web is then dried to obtain a comfortable and fast unidirectional moisture-wicking hydroentangled nonwoven fabric for the sanitary field. The advantages of this design include:

[0023] First, because the initial modulus of viscose fiber is less than that of cotton fiber, its bending strength is also lower. Furthermore, viscose fiber is less fine than cotton fiber, making it softer. Consequently, it is more prone to deformation and slippage when subjected to hydroentangling. Additionally, the pressure of forward hydroentangling is greater than that of reverse hydroentangling, causing the hydroentangling to carry more viscose fiber into the bottom of the mixed fiber web. This results in a gradually increasing gradient distribution of viscose fiber in the post-hydroentangling fiber web (with relatively more cotton fiber at the top and relatively more viscose fiber at the bottom). If the cross-section of the viscose fiber is further defined as a flat or wide structure, the contact area and probability between the viscose fiber and the hydroentangling are even greater, making it easier for the fiber to be carried by the hydroentangling and slippage, thus enhancing the gradient distribution effect.

[0024] Secondly, since viscose fiber has higher moisture absorption properties than cotton fiber, the increasing gradient distribution of viscose fiber from top to bottom in the post-punched fiber web will create a wettability gradient in the thickness of the post-punched fiber web, which is conducive to achieving the unidirectional moisture-wicking properties of nonwoven fabrics.

[0025] Third, since viscose fibers expand by about 50% along the fiber diameter direction after absorbing moisture, the nonwoven fabric forms a differential capillary effect in the thickness direction caused by the pore size gradient (the pore size gradually decreases from the top to the bottom), which further enhances the unidirectional moisture wicking performance of the nonwoven fabric.

[0026] Fourth, the unidirectional moisture-wicking effect in this design relies on purely physical changes and does not involve the introduction of chemical agents, thus making it more environmentally friendly.

[0027] Fifth, the final hydroentangling process in this design further strengthens the mixed fiber web, making the fabric structure more compact and the mesh distribution more uniform after three hydroentangling processes, ensuring that it will not deform during subsequent processing. For example, when hydroentangling is performed on a drum, the resulting pattern or design is less likely to deform.

[0028] Therefore, this invention can not only blend cotton fibers and viscose fibers evenly to produce unidirectional moisture-wicking cotton-containing spunlace nonwoven fabric, but also has strong environmental protection properties.

[0029] 2. In the preparation method of the comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field of this invention, the resulting burred fiber web possesses both differential capillary effect and wettability gradient, allowing water to permeate only from the large pore direction to the small pore direction, while reverse permeation is difficult. Therefore, when this product is applied to sanitary materials such as diapers and sanitary napkins, it can effectively reduce the amount of backflow in the nonwoven fabric, thereby improving the comfort performance of the product. Thus, the present invention exhibits less backflow and higher comfort.

[0030] 3. In the preparation method of the comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field of this invention, since the dry weight ratio of viscose fiber and cotton fiber in the mixed fiber web is 3-4:6-7, the overall proportion of viscose fiber is relatively small. Furthermore, the fibers fed into the carding machine are a composite fiber web formed by the interleaving of cotton fiber web and viscose fiber web. The cotton and viscose fibers in the web are fully separated, avoiding the defects of large differences in carding and mixing caused by different fiber properties in ordinary carding processes. Simultaneously, the multi-layered fiber web superimposed and mixed structure adopted in this invention results in a lower basis weight for each layer of cotton fiber web and viscose fiber web, and more dispersed fibers. This reduces the stress on the surface of the carding teeth in the carding machine, which is conducive to more fine and uniform carding of cotton and viscose fibers, thus making the mixing of cotton and viscose fibers more uniform. Therefore, this invention can not only produce a mixed fiber web, but also make the mixing of cotton and viscose fibers in the mixed fiber web more uniform.

[0031] 4. In the preparation method of the comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field of this invention, due to the low crystallinity and high content of disordered regions of viscose fiber, and the presence of a large number of hydrophilic groups in the [hydroxyl (-OH)] cellulose macromolecules, viscose fiber can adsorb water molecules and perform hydration, resulting in good hygroscopicity and a high moisture regain (approximately 13%). Human skin is most comfortable when its surface moisture content is between 12% and 15%, exhibiting smoothness and elasticity. Therefore, this invention specifically introduces viscose fiber to utilize this characteristic to maintain a comfortable moisture content on the skin surface, keeping the skin in a state of optimal hydration, meeting the moisture requirements of human skin. At high temperatures, this product is breathable and moisture-wicking; at low temperatures, it retains moisture, does not generate static electricity, and remains smooth, soft, and comfortable, particularly conforming to the physiological science of human skin. Therefore, this invention can keep the skin in a state of optimal hydration and comfort, making it especially suitable for application in sanitary materials such as diapers and sanitary napkins, greatly improving the comfort performance of these products. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the cross-section of the viscose fiber in this invention.

[0033] Figure 2 This is a schematic diagram of the structure of the hybrid fiber web in this invention.

[0034] Figure 3 This is a schematic diagram of the structure of the punctured fiber network in this invention.

[0035] Figure 4 This is a schematic diagram illustrating the operation of the concave-convex manufacturing steps in this invention.

[0036] Figure 5 This is a schematic diagram of the pattern on the fabric obtained after the concave-convex manufacturing step in this invention.

[0037] Figure 6 This is a schematic diagram of the distribution of viscose fibers used in this invention before moisture absorption.

[0038] Figure 7 This is a schematic diagram showing the distribution of the viscose fibers used in this invention after absorbing moisture.

[0039] Figure 8 This is a schematic diagram illustrating the fabrication of the overlay mesh in this invention.

[0040] In the diagram: 1. Mixed fiber web, 11. Overlay web, 2. Viscose fiber, 21. Viscose fiber web, 22. Fiber gap, 3. Cotton fiber, 31. Cotton fiber web, 4. Post-punched fiber web, 5. Concave-convex roller, 51. Roller body, 52. Raised pattern, 53. Dent, 6. Spunlace head. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] See Figure 1 — Figure 5 A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for use in the hygiene field, the method comprising the following steps:

[0043] Step 1: Mix viscose fiber 2 and cotton fiber 3 into a web to obtain mixed fiber web 1. In the mixed fiber web 1, the weight of cotton fiber 3 is greater than the weight of viscose fiber 2, and the initial modulus of viscose fiber 2 is less than the initial modulus of cotton fiber 3.

[0044] Step 2: First, perform forward hydroentangling on the mixed fiber web 1 from above. During forward hydroentangling, the viscose fibers 2 are driven by the water jets and slide downwards. After forward hydroentangling is completed, perform reverse hydroentangling on the mixed fiber web 1 from below. Some of the viscose fibers 2 are driven by the water jets and slide upwards. After reverse hydroentangling is completed, perform forward hydroentangling on the mixed fiber web 1 from above to obtain the post-hydroentangled fiber web 4. The hydroentangling pressure of forward hydroentangling is greater than that of reverse hydroentangling. In the post-hydroentangled fiber web 4, the content of viscose fibers 2 shows a gradient distribution trend of gradually increasing from top to bottom.

[0045] Step 3: After drying the spunlace fiber web 4, a comfortable and fast unidirectional moisture-wicking spunlace nonwoven fabric is obtained.

[0046] In the first step, the viscose fiber 2 has a fineness of 0.5-1.2 dtex, and the cotton fiber 3 has a fineness of 1.43-2.22 dtex.

[0047] The weight of the hybrid fiber web 1 is 20-150 g / m².

[0048] In the mixed fiber web 1, the dry weight ratio of the viscose fiber 2 and the cotton fiber 3 is 3-4:6-7.

[0049] In the first step, the process of mixing viscose fiber 2 and cotton fiber 3 to form a web to obtain a mixed fiber web 1 refers to: firstly, opening and removing impurities from viscose fiber 2 and cotton fiber 3 respectively and then mechanically combing them to obtain viscose fiber web 21 and cotton fiber web 31; then, stacking viscose fiber web 21 and cotton fiber web 31 layer by layer to obtain a stacked web 11, wherein the number of viscose fiber web 21 and cotton fiber web 31 in the stacked web 11 is at least one; then, the stacked web 11 is fed into a carding machine through a cotton roller for mixing and carding to obtain a mixed fiber web.

[0050] The number of viscose fiber webs 21 in the superimposed mesh 11 is two, and the number of cotton fiber webs 31 is three. The superimposed order of viscose fiber webs 21 and cotton fiber webs 31 is cotton fiber web 31, viscose fiber web 21, cotton fiber web 31, viscose fiber web 21, and cotton fiber web 31.

[0051] The dry weight ratios of the cotton fiber web 31, viscose fiber web 21, cotton fiber web 31, viscose fiber web 21, and cotton fiber web 31 are: 20-25, 15-20, 10-30, 15-20, and 20-25.

[0052] After the second step is completed, the post-punched fiber web 4 first undergoes a textured surface manufacturing step, and then proceeds to the third step; the textured surface manufacturing step refers to:

[0053] The punctured fiber web 4 is passed around the outer side of the concave-convex roller 5, which includes a roller body 51 and a plurality of protruding patterns 52 thereon. There are pits 53 between adjacent protruding patterns 52. During the process of passing around, the hydroentanglement head 6 located next to the concave-convex roller 5 performs hydroentanglement on the punctured fiber web 4.

[0054] When the water needle passes through the post-punched fiber web 4 and impacts the convex-concave roller 5, if the water needle impacts the convex pattern 52, the fibers above the convex pattern 52 will move towards the depressions and pits 53 in the convex pattern 52, and thus become entangled with each other, thereby reducing the thickness of the post-punched fiber web 4 at that location; if the water needle impacts the pit 53, the water needle will penetrate directly, and the fibers above the pit 53 will move downwards. At the same time, the fibers above the convex pattern 52 will move towards the pit 53 to compress and form a region where longitudinal and transverse fibers are aggregated. Finally, after the hydroentangling is completed, the post-punched fiber web 4 and the convex-concave roller 5 mesh with each other, and a pattern corresponding to the convex pattern 52 is formed on the post-punched fiber web 4.

[0055] The shape of the raised pattern 52 can be any one or any combination of circles, ovals, polygons, stars, animal patterns, and plant patterns.

[0056] A product of a method for preparing a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field, wherein the product is the result of the above-mentioned method for preparing a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field, namely, a comfortable and fast one-way moisture-wicking spunlace nonwoven fabric for the sanitary field.

[0057] The principle of this invention is explained as follows:

[0058] In this invention, cotton fiber 3 refers to cotton fiber obtained by sequentially performing debleaching, washing, and drying. The reason for debleaching the cotton fiber beforehand is that viscose fiber 2 cannot be debleached, and high-temperature debleaching will affect the performance of viscose fiber 2. Therefore, a pre-debleaching process is more suitable. The original cotton fiber is debleached first to obtain cotton fiber 3, and then mixed to prepare fiber web 1.

[0059] The viscose fiber in this invention preferably has a flat or wide cross-section.

[0060] In this invention, the carding machine that feeds cotton rollers into the carding machine is preferably a cover-cylinder type carding machine.

[0061] The viscose fiber used in this invention has excellent moisture absorption properties, which not only meet the physiological requirements of human skin, but also has the characteristics of being smooth and cool, breathable, antistatic, UV resistant, brightly colored, and having high color fastness.

[0062] The viscose fiber used in this invention expands by approximately 50% along its diameter after absorbing moisture, such as... Figure 6 , Figure 7 As shown, Figure 6 Before moisture absorption and expansion, Figure 7 After moisture absorption and expansion, a comparison between the fiber gaps 22 in the two figures shows that the fiber gaps 22 are significantly reduced after moisture absorption and expansion, which is beneficial for constructing a "macropore-micropore" structure.

[0063] The reason why the dry weight ratio of viscose fiber 2 and cotton fiber 3 in the mixed fiber web 1 of this invention is 3-4:6-7 is that: with this ratio of viscose / cotton fiber mixing, there is less viscose fiber and more cotton fiber, which ensures the skin-friendly comfort of the product when it is used in hygiene materials such as diapers and sanitary napkins; at the same time, since the mixing ratio of viscose fiber is 30-40%, which is relatively small, and the fiber fed into the carding machine is a composite fiber web formed by the cross-combination of cotton and viscose fiber webs, the cotton fiber and viscose fiber in the fiber web are fully separated, avoiding the defects of large differences in carding and mixing caused by different fiber properties in ordinary carding processes.

[0064] In this invention, the dry weight ratios of the five-layer structure—cotton web 31, viscose web 21, cotton web 31, viscose web 21, and cotton web 31—are limited to 20-25, 15-20, 10-30, 15-20, and 20-25, respectively, because:

[0065] By employing a multi-layered fiber web structure with different proportions, cotton and viscose fibers are dispersed into multiple layers, resulting in a lower basis weight and more dispersed fibers in each layer of the cotton and viscose fiber web. This reduces the stress on the surface of the carding teeth in the carding machine, which in turn facilitates finer and more uniform carding of cotton and viscose fibers, resulting in a more uniform mixing of cotton and viscose fibers.

[0066] Example 1:

[0067] See Figure 1 — Figure 5A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for use in the hygiene field, the method comprising the following steps:

[0068] Step 1: Mix viscose fiber 2 and cotton fiber 3 into a web to obtain mixed fiber web 1. In the mixed fiber web 1, the weight of cotton fiber 3 is greater than the weight of viscose fiber 2, and the initial modulus of viscose fiber 2 is less than the initial modulus of cotton fiber 3.

[0069] Step 2: First, perform forward hydroentangling on the mixed fiber web 1 from above. During forward hydroentangling, the viscose fibers 2 are driven by the water jets and slide downwards. After forward hydroentangling is completed, perform reverse hydroentangling on the mixed fiber web 1 from below. Some of the viscose fibers 2 are driven by the water jets and slide upwards. After reverse hydroentangling is completed, perform forward hydroentangling on the mixed fiber web 1 from above to obtain the post-hydroentangled fiber web 4. The hydroentangling pressure of forward hydroentangling is greater than that of reverse hydroentangling. In the post-hydroentangled fiber web 4, the content of viscose fibers 2 shows a gradient distribution trend of gradually increasing from top to bottom.

[0070] Step 3: After drying the spunlace fiber web 4, a comfortable and fast unidirectional moisture-wicking spunlace nonwoven fabric is obtained.

[0071] A product of a method for preparing a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field, wherein the product is the result of the above-mentioned method for preparing a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field, namely, a comfortable and fast one-way moisture-wicking spunlace nonwoven fabric for the sanitary field.

[0072] The parameters of the above-mentioned viscose fiber 2 and cotton fiber 3 are shown in the table below:

[0073]

[0074] Example 2:

[0075] The basic content is the same as in Example 1, except that:

[0076] The weight of the hybrid fiber web 1 is 20-150 g / m².

[0077] Example 3:

[0078] The basic content is the same as in Example 1, except that:

[0079] In the mixed fiber web 1, the dry weight ratio of the viscose fiber 2 and the cotton fiber 3 is 3-4:6-7.

[0080] Example 4:

[0081] The basic content is the same as in Example 1, except that:

[0082] In the first step, the cross-section of the viscose fiber 2 is a flat or wide-band structure. For example... Figure 1 As shown, this is viscose fiber 2 with a flat cross-section.

[0083] Example 5:

[0084] The basic content is the same as in Example 1, except that:

[0085] See Figure 8 In the first step, the process of mixing viscose fiber 2 and cotton fiber 3 to form a web to obtain a mixed fiber web 1 refers to: firstly, opening and removing impurities from viscose fiber 2 and cotton fiber 3 respectively and then mechanically combing them to obtain viscose fiber web 21 and cotton fiber web 31; then, stacking viscose fiber web 21 and cotton fiber web 31 layer by layer to obtain a stacked web 11, wherein the number of viscose fiber web 21 and cotton fiber web 31 in the stacked web 11 is at least one; then, the stacked web 11 is fed into a carding machine through a cotton roller for mixing and carding to obtain the mixed fiber web 1.

[0086] The preferred superimposed web 11 has a five-layer structure, including cotton fiber web 31, viscose fiber web 21, cotton fiber web 31, viscose fiber web 21, and cotton fiber web 31 stacked in sequence, with their corresponding dry weight ratios being 20-25, 15-20, 10-30, 15-20, and 20-25 (each layer of web is the same size).

[0087] Example 6:

[0088] The basic content is the same as in Example 5, except that:

[0089] The five-layer fiber web has a basis weight of 17.70 g / m², 14.75 g / m², 7.08 g / m², 14.75 g / m², and 17.70 g / m² at standard moisture regain (each layer of the fiber web is the same size). Subsequently, the mixed, stacked web 11 is fed into a flatbed-cylinder carding machine via a cotton feed roller for mixing and carding, and the mixed fiber web is laid out to obtain a mixed fiber web 1 with a basis weight of 80 g / m².

[0090] Example 7:

[0091] The basic content is the same as in Example 1, except that:

[0092] like Figure 4As shown, after the second step, the punctured fiber web 4 first undergoes a convex-concave manufacturing step, and then proceeds to the third step; the punctured fiber web 4 is wrapped around the outer side of the convex-concave roller 5, which includes a roller body 51 and a plurality of protruding patterns 52 disposed thereon, with pits 53 between adjacent protruding patterns 52. During the wrapping process, the hydroentangling head 6 located beside the convex-concave roller 5 performs hydroentangling on the punctured fiber web 4; when the water needle passes through the punctured fiber web 4 and impacts the convex-concave roller 5, if the water needle impacts the protruding pattern 52, the protruding pattern 53 will be located on the outer side of the roller 5. The fibers above 2 will move towards the recesses in the raised pattern 52 and the pits 53, causing them to entangle with each other, thereby reducing the thickness of the post-punching fiber web 4 at that location. If the water jet hits the pit 53, the water jet will penetrate directly, and the fibers above the pit 53 will move downwards. At the same time, combined with the aforementioned movement of the fibers above the raised pattern 52 towards the pit 53, they will be compressed to form a region where longitudinal and transverse fibers are aggregated. Finally, after the hydroentangling is completed, the post-punching fiber web 4 meshes with the convex-concave roller 5, forming a pattern on the post-punching fiber web 4 corresponding to the raised pattern 52, such as... Figure 5 As shown.

[0093] The aforementioned uneven structure can improve the fluffiness and fullness of the final nonwoven fabric, which is conducive to the penetration of moisture into the interior of the nonwoven fabric, greatly improving its water absorption performance and making it more effective in unidirectional moisture wicking.

[0094] The above description is only a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the content disclosed in the present invention should be included within the scope of protection set forth in the claims.

Claims

1. A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for use in the hygiene field, characterized in that: The preparation method includes the following steps: Step 1: Mix viscose fiber (2) and cotton fiber (3) into a web to obtain a mixed fiber web (1). In the mixed fiber web (1), the weight of cotton fiber (3) is greater than the weight of viscose fiber (2), and the initial modulus of viscose fiber (2) is less than the initial modulus of cotton fiber (3). Step 2: First, perform forward hydroentangling on the mixed fiber web (1) from above. During forward hydroentangling, the viscose fiber (2) is driven by the water needle and slides downward. After forward hydroentangling is completed, perform reverse hydroentangling on the mixed fiber web (1) from below. Some of the viscose fiber (2) is driven by the water needle and slides upward. After reverse hydroentangling is completed, perform forward hydroentangling on the mixed fiber web (1) from above to obtain the post-hydroentangling fiber web (4). The hydroentangling pressure of forward hydroentangling is greater than that of reverse hydroentangling. In the post-hydroentangling fiber web (4), the content of viscose fiber (2) shows a gradient distribution trend of gradually increasing from top to bottom, with relatively more cotton fiber in the top layer and relatively more viscose fiber in the bottom layer. The fineness of the viscose fiber is less than that of the cotton fiber. Step 3: After drying the punctured fiber web (4), a comfortable and fast unidirectional moisture-wicking spunlace nonwoven fabric is obtained.

2. The method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 1, characterized in that: In the first step, the viscose fiber (2) has a fineness of 0.5-1.2 dtex, and the cotton fiber (3) has a fineness of 1.43-2.22 dtex.

3. A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 1 or 2, characterized in that: The weight of the hybrid fiber web (1) is 20-150 g / m².

4. A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 1 or 2, characterized in that: In the mixed fiber web (1), the dry weight ratio of the viscose fiber (2) and the cotton fiber (3) is 3-4:6-7.

5. A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 1 or 2, characterized in that: In the first step, the process of mixing viscose fiber (2) and cotton fiber (3) into a web to obtain a mixed fiber web (1) refers to: firstly, opening and removing impurities from viscose fiber (2) and cotton fiber (3) and mechanically combing them to obtain viscose fiber web (21) and cotton fiber web (31), and then stacking the viscose fiber web (21) and cotton fiber web (31) layer by layer to obtain a stacked web (11). The number of viscose fiber web (21) and cotton fiber web (31) in the stacked web (11) is at least one. Then, the stacked web (11) is fed into a carding machine by a cotton roller for mixed combing to obtain a mixed fiber web.

6. The method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 5, characterized in that: The number of viscose fiber webs (21) in the superimposed web (11) is two layers, and the number of cotton fiber webs (31) is three layers. The superimposed order of viscose fiber webs (21) and cotton fiber webs (31) is cotton fiber webs (31), viscose fiber webs (21), cotton fiber webs (31), viscose fiber webs (21), and cotton fiber webs (31).

7. The method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 6, characterized in that: The dry weight ratios of the cotton fiber web (31), viscose fiber web (21), cotton fiber web (31), viscose fiber web (21), and cotton fiber web (31) are: 20-25, 15-20, 10-30, 15-20, and 20-25.

8. A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 1 or 2, characterized in that: After the second step is completed, the burred fiber web (4) first undergoes a textured surface manufacturing step, and then proceeds to the third step; the textured surface manufacturing step refers to: The punctured fiber web (4) is passed around the outer side of the convex-concave roller (5), which includes a roller body (51) and a plurality of protruding patterns (52) provided thereon. There are pits (53) between adjacent protruding patterns (52). During the process of passing around, the spunlace head (6) located next to the convex-concave roller (5) performs hydrospunlace on the punctured fiber web (4). When the water needle passes through the post-punching fiber mesh (4) and impacts the concave-convex roller (5), if the water needle impacts the protruding pattern (52), the fibers above the protruding pattern (52) will move towards the depression in the protruding pattern (52) and the pit (53), so as to entangle with each other, thereby reducing the thickness of the post-punching fiber mesh (4) at that point; if the water needle impacts the pit (53), the water needle will penetrate directly, and the fibers above the pit (53) will move downward. At the same time, the fibers above the protruding pattern (52) will move towards the pit (53) to compress and form a longitudinal and transverse fiber aggregation area. Finally, after the water punching is completed, the post-punching fiber mesh (4) and the concave-convex roller (5) mesh with each other and form a pattern on the post-punching fiber mesh (4) corresponding to the protruding pattern (52).

9. A method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field according to claim 8, characterized in that: The shape of the protruding pattern (52) is any one or any combination of a circle, an oval, a polygon, a star, an animal pattern, and a plant pattern.

10. A product of a method for preparing a comfortable unidirectional moisture-wicking nonwoven fabric for the sanitary field, characterized in that: The product is the result of the preparation method of a comfortable one-way moisture-wicking nonwoven fabric for the sanitary field as described in claim 1, namely, a comfortable and fast one-way moisture-wicking spunlace nonwoven fabric for the sanitary field.

Images