Nonwoven fabric structure and method for manufacturing the same

Abstract

The present invention relates to a nonwoven fabric structure and a method for manufacturing the same, the nonwoven fabric structure including first fibers and second fibers, the first fibers including one or more components selected from the group consisting of rayon, cellulose, polyester, and polyamide, and the second fibers being bi-component fibers including synthetic resin components having different heat shrinkage rates from each other.

Description

Technical Field

[0001] This invention relates to nonwoven fabric structures and their manufacturing methods, specifically to nonwoven fabric structures with excellent dust adsorption and capture capabilities, and their manufacturing methods. Background Technology

[0002] Nonwoven fabric refers to fabrics made by bonding fibers into a mesh using chemical or mechanical methods, rather than by weaving or knitting them. Nonwoven fabrics possess various physical properties depending on their composition, and can achieve various textures by effectively adjusting their surface characteristics. Through the entanglement of fibers within their structure, nonwoven fabrics include spaces for communication with external substances such as air and fluids including water. Based on this property, nonwoven fabrics are used as charging materials or can be used as trapping materials, and are also used as a base material for cleaning and sanitation.

[0003] In the past, wet nonwoven fabric products used as wet wipes, cleaning cloths, and rags could not effectively absorb dust from the surface of the object being used, or the wet nonwoven fabric products themselves had poor trapping power, resulting in the problem of the trapped dust falling back off the product surface.

[0004] To address this issue, products have been developed that increase the dust adsorption area of ​​nonwoven fabrics by using microfibers to manufacture them or by creating embossing patterns on the fabric. While these products show a slight increase in dust adsorption performance, this performance is not significant enough to warrant a meaningful increase. The insufficient capture capacity leads to the problem of captured dust falling off and re-contaminating the cleaned surface. Summary of the Invention

[0005] The problem that the invention aims to solve

[0006] This invention was developed to solve the problems of the prior art as described above. The purpose of this invention is to provide a nonwoven fabric structure with various structures that have both dust adsorption and dust capture functions, and a method for manufacturing each nonwoven fabric structure.

[0007] Methods for solving problems

[0008] The present invention provides a nonwoven fabric structure comprising a first fiber and a second fiber, wherein the first fiber comprises one or more components selected from the group consisting of rayon, cellulose, polyester and polyamide, and the second fiber is a bicomponent fiber comprising synthetic resin components with different heat shrinkage rates.

[0009] Specifically, the nonwoven structure includes: a first layer comprising the first fiber; and a second layer comprising the second fiber, wherein the first layer is laminated onto at least one side of the second layer, and the first layer and the second layer are bonded together by a hydroentangling process.

[0010] Specifically, the second layer has a greater surface roughness compared to the first layer.

[0011] Specifically, the surface roughness R along the centerline of the first layer and the second layer mentioned above. a The ratio is 1:1.1 to 1:5.

[0012] Specifically, the ten-point average unevenness R of the first and second layers mentioned above. z The ratio is 1:1.1 to 1:5.

[0013] Specifically, the aforementioned nonwoven fabric structure is a single-layer structure formed by manufacturing a nonwoven fabric mesh through a hydroentangling process, wherein the nonwoven fabric mesh is formed by mixing the aforementioned first fiber and the aforementioned second fiber.

[0014] Specifically, in the above-mentioned nonwoven fabric mesh, the first fiber and the second fiber are mixed in a weight ratio of 1:1 to 3:2.

[0015] Specifically, in the above-mentioned hydroentangling process, water is sprayed at a pressure of 40 bar to 60 bar from nozzles with holes having a diameter of 0.09 mm to 0.5 mm and arranged at intervals of 0.3 mm to 0.6 mm.

[0016] Specifically, in the aforementioned bicomponent fiber, synthetic resin components with different heat shrinkage rates are configured in a core-sheath structure, and the core is disposed off-center from the sheath.

[0017] Specifically, the aforementioned bicomponent fiber includes two or more synthetic resin components selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polypropylene terephthalate, poly(1,4-cyclohexanedimethyl terephthalate) and nylon.

[0018] In addition, the present invention provides a method for manufacturing a nonwoven structure, characterized by comprising the following steps: (1) forming a fiber mesh, the fiber mesh comprising a first fiber and a second fiber, the first fiber comprising one or more components selected from the group consisting of rayon, cellulose, polyester and polyamide, and the second fiber being a bicomponent fiber comprising synthetic resin components with different heat shrinkage rates; (2) performing a hydroentangling process on the fiber mesh formed in step (1) to form a nonwoven structure; and (3) drying the nonwoven structure formed in step (2) at 120 to 200°C.

[0019] Specifically, step (1) above includes the following steps: combing the first fiber to form a first mesh; combing the second fiber to form a second mesh; and stacking the first mesh onto at least one face of the second mesh.

[0020] Specifically, step (1) above includes the following steps: mixing the first fiber and the second fiber; and combing the mixed fibers to form a fiber mesh.

[0021] Specifically, the first fiber and the second fiber are mixed in a weight ratio of 1:1 to 3:2.

[0022] Specifically, in the manufacturing method of the nonwoven structure, during the hydroentangling process described above, water is sprayed at a pressure of 40 bar to 60 bar from nozzles having holes with a diameter of 0.09 mm to 0.5 mm and arranged at intervals of 0.3 mm to 0.6 mm.

[0023] Specifically, in the manufacturing method of the nonwoven structure, the aforementioned bicomponent fibers are configured with synthetic resin components with different heat shrinkage rates in a core-sheath structure, and the core is disposed off-center from the sheath.

[0024] Specifically, in the manufacturing method of the nonwoven structure, the aforementioned bicomponent fiber includes two or more synthetic resin components selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polypropylene terephthalate, poly(1,4-cyclohexanedimethyl terephthalate) and nylon.

[0025] Invention Effects

[0026] According to one embodiment of the present invention, the nonwoven fabric structure has an adsorption layer that can adsorb foreign objects such as dust and a capture layer that captures the adsorbed foreign objects such as dust, thereby improving the dust adsorption performance while preventing the adsorbed dust from falling off the structure.

[0027] In one embodiment of the nonwoven fabric structure of the present invention, the adsorption layer provides soft wipeability, and the trapping layer provides dust trapping power while forming a rough surface to provide a scrubbing effect on the object surface.

[0028] In one embodiment of the present invention, the nonwoven fabric structure is composed of a single layer and has both adsorption and capture functions for foreign objects such as dust, thereby improving the dust adsorption performance while keeping the adsorbed dust from falling off the structure.

[0029] An embodiment of the present invention provides a nonwoven structure through a hydroentangling process, which provides a nonwoven structure without the need for an adhesive, and the manufactured nonwoven structure has the adsorption and capture effects described above. Attached Figure Description

[0030] Figure 1 (a) and (b) are cross-sectional views showing the bicomponent fibers used in a nonwoven structure according to an embodiment of the present invention.

[0031] Figure 2 This is a conceptual diagram of a nonwoven fabric structure according to an embodiment of the present invention.

[0032] Figure 3 This is a conceptual diagram of a nonwoven fabric structure according to an embodiment of the present invention.

[0033] Figure 4 This is a conceptual diagram illustrating the process for manufacturing a nonwoven structure according to an embodiment of the present invention.

[0034] Figure 5 This is a conceptual diagram illustrating the process for manufacturing a nonwoven structure according to an embodiment of the present invention.

[0035] Figure 6 This is a scanning electron microscope image of the cortex in a bicomponent fiber contained in a nonwoven structure according to an embodiment of the present invention.

[0036] Figure 7 These are photographs comparing the bulkiness of (a) a nonwoven structure of an embodiment of the present invention and (b) a nonwoven structure of a comparative example, each stacked with 15 sheets, when pressure is applied.

[0037] Figure 8 These are 3D depth composite images of (a) one side of the structure of Embodiment 1 of the present invention and (b) one side of the structure of Comparative Example 1.

[0038] Figure 9 The images are (a) scanning electron microscope images, (b) optical microscope images confirming the dust-trapping performance of a nonwoven fabric structure according to an embodiment of the present invention, and (c) scanning electron microscope images, (d) optical microscope images confirming the dust-trapping performance of a nonwoven fabric structure according to a comparative example.

[0039] Figure 10 These are images confirming the erasability of (a) a nonwoven structure of an embodiment of the present invention and (b) a nonwoven structure of a comparative example.

[0040] (Symbol Explanation)

[0041] A: Component 1 B: Component 2

[0042] 1, 2: Nonwoven fabric structure

[0043] 10: Level 1 20: Level 2

[0044] 30: Hybrid nonwoven mesh

[0045] 100, 200: Nonwoven fabric manufacturing equipment

[0046] 110, 210: First Fiber Supply Department

[0047] 120, 220: Second Fiber Supply Department

[0048] 130, 230: Comb

[0049] 140, 240: Water flow connector

[0050] 150, 250: Dryer

[0051] 160, 260: Calendering machine

[0052] 170, 270: Winding machine Detailed Implementation

[0053] The object, specific advantages, and novel features of the present invention will be clearly understood by referring to the following detailed description and preferred embodiments. However, these embodiments are for illustrative purposes only, and the scope of the invention is not limited to these embodiments. Furthermore, in describing the present invention, detailed descriptions of relevant prior art have been omitted where it is determined that a detailed description of such art would obscure the essence of the invention.

[0054] Below, high pressure, low pressure, high temperature, and low temperature are relative terms, not absolute values.

[0055] Below, the roughness of the nonwoven fabric structure is used as the surface unevenness of the aforementioned nonwoven fabric structure. The center line average height (Ra) and ten-point average unevenness (R0) are compared. z The surface roughness is quantified into more than one roughness. The surface roughness R along the centerline is... a The calculated average roughness is obtained by dividing the sum of the absolute values ​​of the distances from each position on a cross-section of the object's surface relative to the assumed centerline by the number of that position. Ten-point average roughness R z It represents the average distance between the five highest peaks and five lowest valleys of a cross section of the object's surface relative to the assumed centerline.

[0056] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0057] Figure 1 This is a conceptual diagram showing a cross-section of a bicomponent fiber used in a nonwoven fabric structure according to an embodiment of the present invention. Figure 2 and 3 These are conceptual diagrams illustrating a nonwoven fabric structure according to any embodiment of the present invention.

[0058] An embodiment of the nonwoven fabric structure of the present invention includes a first fiber and a second fiber. The first fiber includes one or more components selected from the group consisting of rayon, cellulose, polyester and polyamide. The second fiber is a bicomponent fiber including synthetic resin components with different heat shrinkage rates.

[0059] Reference Figure 1 The bicomponent fiber is a fiber comprising two synthetic resin components of different kinds, preferably wherein the two synthetic resin components have different thermal shrinkage rates when exposed to a specified temperature.

[0060] The bicomponent fiber is composed of two different types of synthetic resin components arranged in a sheath-core structure. Specifically, component A, located in the core portion, is positioned off-center from component B, located in the sheath portion. The off-center positioning of component A and component B can be explained as follows... Figure 1 (a) is formed in such a way as to connect with the edge of the second component B, but is not limited to this, it can also be formed as follows: Figure 1 (b) Thus, they are arranged at a certain distance from the edge of the second component B. The first component A and the second component B are components with different thermal shrinkage rates when exposed to a specified temperature, but this does not mean that a particular component necessarily has a higher shrinkage rate. It is possible that the first component A, located in the core, has a higher thermal shrinkage rate, or that the second component B, located in the skin, has a higher thermal shrinkage rate.

[0061] By positioning the core eccentrically on the sheath, the bicomponent fibers are exposed to a specified temperature, causing the component with a relatively larger thermal shrinkage rate to induce a relatively larger shrinkage value in length. This results in at least a portion of the entire bicomponent fiber deforming into a folded or coiled shape. The aforementioned thermal shrinkage rate arises from the difference in melting points of the individual components. That is, shrinkage in the bicomponent fiber is induced by the partial melting and hardening of the sheath or core. Such deformation induction of the bicomponent fiber includes changes in the fiber mesh of the bicomponent fiber or the surface roughness of the nonwoven fabric, as well as the bulkiness of the nonwoven fabric.

[0062] The first component A and the second component B constituting the bicomponent fiber are synthetic resin components selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polypropylene terephthalate, poly(1,4-cyclohexanedimethyl terephthalate) and nylon.

[0063] Reference Figure 2 According to one embodiment of the present invention, the nonwoven fabric structure 1 includes a first layer 10 including a first fiber and a second layer 20 including a second fiber. It can be a multilayer nonwoven fabric structure in which the first layer 10 is stacked on at least one side of the second layer 20.

[0064] The first fiber comprises 60% to 100% of the total weight of the first layer 10. Preferably, the first layer 10 consists only of the first fiber. The second fiber comprises 60% to 100% of the total weight of the second layer 20. Preferably, the second layer 20 consists only of the second fiber. The diameter of the first fiber is smaller than the diameter of the second fiber.

[0065] For example, the nonwoven fabric structure 1 in this embodiment is a double-layer nonwoven fabric structure formed by stacking a first layer 10 composed only of the first fiber and a second layer 20 composed only of the second fiber.

[0066] The first layer 10 is stacked on at least one face of the second layer 20, but is not limited thereto. In a modified embodiment of this embodiment, the first layer is stacked such that it covers at least a portion of any face of the second layer or such that it covers all faces of the second layer while only covering a portion of the other faces (not shown).

[0067] The first layer 10 and the second layer 20 are joined together by a spunlace process. In this invention, spunlace is a process in which water jets are sprayed onto one or more fiber meshes to induce entanglement between the fibers constituting the fiber mesh, thereby joining the internal fibers of the fiber mesh or other fiber meshes. Therefore, the nonwoven structure of this embodiment is formed by spraying water jets onto at least one surface to join the two layers together, with the fiber mesh formed by the first fiber (i.e., the first layer 10) and the fiber mesh formed by the second fiber (i.e., the second layer 20) stacked.

[0068] In the hydroentangling process, water is sprayed at a pressure of 40 bar to 60 bar from nozzles with orifices having a diameter of 0.09 mm to 0.5 mm and arranged at intervals of 0.3 mm to 0.6 mm. Preferably, the diameter of the nozzle orifices is 0.09 mm to 0.3 mm, and the water spraying pressure is 45 bar to 55 bar. Water is sprayed onto both sides of the stacked fiber mesh in the hydroentangling process to bond the fiber mesh together. The diameter of the nozzle orifices, the nozzle arrangement intervals, and the spraying time for spraying water onto both sides may be the same or different.

[0069] In the nonwoven fabric structure of this embodiment, the first layer 10 and the second layer 20 are joined by a hydroentangling process, possessing a suitable stiffness for wiping the surface of an object to attract dust. The stiffness of the nonwoven fabric structure is evaluated by measuring the bending length in a cantilever beam manner. For example, in the nonwoven fabric structure of this embodiment, the average value of the bending length relative to the MD and CD directions is 5 or more. When the average value is 5 or more, the structure can maintain a stable shape even when wiping a hard surface; when it is less than 5, it is impossible to ensure the safety of the shape required for dust attraction and capture, such as permanent deformation of the appearance due to wiping. Preferably, the nonwoven fabric structure has an average value of 5 to 10, and most preferably, it has an average value of 7 to 10.

[0070] The nonwoven structure of this embodiment is obtained by a drying or heating process after the hydroentangling process. At least one surface of the nonwoven structure is heated and maintained at a predetermined temperature, thereby stimulating the different thermal shrinkages of the components in the bicomponent fibers. As a result, the shape and properties of the surface of the second layer 20 in the nonwoven structure change. As the bicomponent fibers included in the second layer 20 are bent or wound, the second layer 20 deforms to have a relatively larger surface roughness than the first layer 10. Therefore, in the nonwoven structure 1 of this embodiment, the second layer 20 has a larger surface roughness than the first layer 10.

[0071] Additionally, as the bicomponent fibers are bent or entangled, the second layer 20 forms channels within it that allow external substances such as fluids or dust to communicate. Through this structure, foreign substances such as air, water, and dust are captured or adsorbed into the second layer 20 and then flow into these channels, remaining in a captured state or in a state of being captured.

[0072] For example, the surface roughness R along the centerline of layer 10 and layer 20. a The ratio is from 1:1.1 to 1:5, with a ten-point average unevenness R for layer 1 (10) and layer 2 (20). z The ratio is between 1:1.1 and 1:5. Centerline surface roughness R a Or the ten-point average unevenness R z When the ratio is less than 1:1.1, the dust adsorption and capture effect of the second layer 20 cannot be sufficiently ensured; when it is greater than 1:1.5, the retention force of the adsorbed state decreases. Preferably, the surface unevenness R along the center line of the first layer 10 and the second layer 20 is... a The ratio is between 1:1.2 and 1:4, with a ten-point average unevenness R for layer 1 (10) and layer 2 (20). z The ratio is from 1:1.2 to 1:4. More preferably, the surface roughness R along the centerline of the first layer 10 and the second layer 20 is...a The ratio is 1:1.5 to 1:4, with a ten-point average unevenness R for layer 1 (10) and layer 2 (20). z The ratio is from 1:1.5 to 1:4. Most preferably, the surface unevenness R along the centerline of the first layer 10 and the second layer 20 is... a The ratio is 1:2 to 1:3, and the ten-point average unevenness R of layer 1 (10) and layer 2 (20) is... z The ratio is between 1:2 and 1:3.

[0073] In the nonwoven fabric structure 1 of this embodiment as described above, the first layer 10 is constructed with a relatively lower roughness, thus the relatively soft first layer 10 serves as an adsorption layer that uses electrostatics to adsorb fine particles such as dust. The second layer 20, in a dry state, adsorbs dust through triboelectricity; in a wet state, it adsorbs dust through one or more of the viscosity of the impregnated cleaning liquid, surfactants, surface tension, and capillary action, and serves as a trapping layer by forming a channel structure to capture the adsorbed substances. Furthermore, the second layer is constructed with a relatively higher roughness, allowing the user to wipe the object surface using a relatively rough surface, thereby providing a scrubbing effect to remove stains or contaminants through physical force.

[0074] For example, when a user uses the second layer 20 of the nonwoven fabric structure 1 to wipe the surface of an object, the hardened stains are physically removed. The first layer 10 moves back and forth on the surface of the object, thereby adsorbing dust and fragments of stains that have been broken by the wiping, and even dust, thus providing a new space for capturing the dust adsorbed by the second layer 20.

[0075] Reference Figure 3 One embodiment of the present invention is a nonwoven fabric structure that is a single-layer nonwoven fabric structure used to manufacture a nonwoven fabric mesh 30 formed by mixing the first fiber and the second fiber through a hydroentangling process.

[0076] The following describes the nonwoven fabric structure 2, regarding its relationship with... Figure 2 The description of the repeated parts of the nonwoven structure 1 can be replaced by the above embodiments.

[0077] The nonwoven mesh 30 is formed by mixing the first fiber and the second fiber. The fibers are woven separately and then mixed during the carding process, or the first and second fibers can be mixed together and woven before carding. The nonwoven mesh 30 mixes the first fiber and the second fiber in a weight ratio of 1:1 to 3:2.

[0078] For example, the nonwoven structure 2 in this embodiment is a single-layer nonwoven structure composed of a nonwoven mesh 30 formed by mixing the first fiber and the second fiber in a predetermined ratio.

[0079] A nonwoven mesh 30, formed by mixing the first and second fibers, is induced to bond between the fibers within the nonwoven mesh through a hydroentangling process to form a structure. In the nonwoven structure 2 of this embodiment, a structure is formed by spraying a water jet onto at least one surface of the nonwoven mesh 30, which is formed by mixing the first and second fibers.

[0080] The nonwoven structure of this embodiment is produced by a drying or heating process after the hydroentangling process. As a result, the roughness of at least one surface of the nonwoven structure 2 is deformed to be rougher than before drying or heating.

[0081] As described above, the nonwoven fabric structure 2 of this embodiment is formed as a single-layer structure including a first fiber and a second fiber, serving as both an adsorption layer and a trapping layer. In a dry state, the adsorption layer, with its surface being the second layer 20 of the nonwoven fabric structure 1 described above, adsorbs fine particles such as dust using triboelectricity or, in a wet state, using the viscosity of the impregnated cleaning liquid, surfactants, surface tension, and capillary action. The trapping layer provides trapping of adsorbed substances through a channel structure formed by the deformation of the second fiber. Depending on the conditions of the drying or heating process, at least a portion of any surface of the nonwoven fabric structure 2 possesses a relatively high roughness relative to the remaining portion. Therefore, when a user scrubs the object surface with the relatively rough surface, a scrubbing effect is provided by physical force to remove stains or contaminants.

[0082] For example, the user can use any side of the nonwoven fabric structure 2 to wipe the surface of the object to physically remove hardened stains, and to absorb and capture dust and fragments of stains and even dust that have been damaged by the wiping.

[0083] Figure 4 and 5 These are conceptual diagrams illustrating the manufacturing process of a nonwoven fabric structure according to any embodiment of the present invention.

[0084] Reference Figure 4 A nonwoven fabric manufacturing apparatus 100 is provided for manufacturing a nonwoven fabric structure 1 according to an embodiment of the present invention.

[0085] The nonwoven fabric manufacturing apparatus 100 includes a carder 130, a water flow connector 140, a dryer 150, a calender 160, and a winding machine 170, etc.

[0086] The first fiber supply unit 110 and the second fiber supply unit 120 supply the first fiber and the second fiber to the nonwoven fabric manufacturing apparatus 100, respectively. Each supply unit supplies the fibers in the open-weave state to the carding unit 130, but is not limited thereto.

[0087] The carder 130 is a device that untangles the received individual fibers and adjusts the fiber orientation; for example, it can be a flat card, roller card, or combined card, but is not limited to these. A mesh forming machine (not shown) is included at the rear end of the carder 130 to form a mesh shape from the carded fibers. The meshes of the first fiber and the second fiber, having passed through the carder 130, are arranged in a stacked manner and supplied to the water flow connector 140.

[0088] The water jet connector 140 moves the stacked mesh and sprays water jets onto at least one face of the mesh to perform a hydroentangling process. In this embodiment, the water jet connector 140 sprays water at a pressure of 40 to 60 bar from nozzles having diameter holes of 0.09 to 0.5 mm and spaced at intervals of 0.3 to 0.6 mm. After passing through the water jet connector 140, the nonwoven structure 1 has a double structure formed by combining the first layer 10 and the second layer 20, and is then supplied to the dryer 150.

[0089] Dryer 150 is a component that dries water sprayed during water flow, but it is not limited to this. Additional heating can also deform the second layer 20, changing its surface properties. The second fiber of the second layer 20, i.e., the bicomponent fiber, shrinks differently between component A and component B, thereby stimulating bending or entanglement of the bicomponent fibers and increasing the surface roughness of the second layer 20. The nonwoven structure 1 after passing through dryer 150 is then supplied to calender 160.

[0090] The calender 160 calenders the manufactured nonwoven structure 1 using one or more rollers. These rollers can perform functions such as pressing, heating, or both. Only one pair of rollers is shown in the figure, but multiple rollers or pairs can also be configured. The rollers can be configured in forms known in the art, such as L-shaped, Z-shaped, or inverted L-shaped, but are not limited to these. The calender 160 can form desired textures or imprints on the surface of the nonwoven structure 1. The deformation of the second layer 20 in the dryer 150 can also occur in the calender 160. The nonwoven structure 1, after passing through the calender 160, is fed to the winding machine 170 and formed into a curled state.

[0091] Based on the above description of the nonwoven fabric manufacturing apparatus 100 of this embodiment, a method for manufacturing a nonwoven fabric structure 1 using the above-described apparatus will be described.

[0092] The method for manufacturing the nonwoven structure 1 includes the following steps (1) to (3): (1) forming a fiber mesh having a first fiber comprising one or more components selected from the group consisting of rayon, cellulose, polyester and polyamide, and a second fiber comprising a bicomponent fiber comprising synthetic resin components with different heat shrinkage rates; (2) performing a hydroentangling process on the fiber mesh formed in step (1) to form a nonwoven structure; and (3) drying the nonwoven structure formed in step (2) at 120 to 200°C.

[0093] (1) Step is the step of supplying the first fiber and the second fiber to the nonwoven fabric manufacturing apparatus 100. Therefore, (1) step also includes: the step of combing the first fiber 130 to form a first mesh, the step of combing the second fiber 130 to form a second mesh, and the step of stacking the first mesh onto at least one side of the second mesh.

[0094] (2) The step is to spray a water jet by passing the stacked mesh through the water jet connector 140. The nozzle used for water jet spraying and the water spraying conditions are the same as described above.

[0095] (3) The step is to dry the nonwoven structure 1, which is to induce the deformation of the bicomponent fibers of the second layer by passing through at least one of the dryer 150 and the calender 160.

[0096] Reference Figure 5 The nonwoven fabric manufacturing apparatus 200 used for manufacturing a nonwoven fabric structure 2 according to an embodiment of the present invention will be described.

[0097] The nonwoven fabric manufacturing apparatus 200 includes a carding machine 20, a water flow connector 240, a dryer 250, a calender 260, and a winding machine 270. The nonwoven fabric manufacturing apparatus 200 and the method for manufacturing a nonwoven fabric structure 2 using this apparatus 200 will be described below. Regarding the... Figure 4 The repeated parts of the manufacturing apparatus 100 and method for the nonwoven structure 1 will be omitted and replaced by the above embodiments.

[0098] The first fiber supply unit 210 and the second fiber supply unit 220 respectively supply the first fiber and the second fiber to the nonwoven fabric manufacturing apparatus 200. The first fiber and the second fiber can be in a mixed state before being supplied to the apparatus. As long as the uniform mixing of the first fiber and the second fiber is ensured, the method or apparatus is not limited. The mixed first fiber and the second fiber are then supplied to the carding machine 230.

[0099] The comber 230 forms a fiber mesh in the form of a mixture of the first and second fibers, and supplies this to the water flow connector 240.

[0100] The water jet connector 240 sprays water jets onto at least one side of the fiber mesh to perform the hydroentangling process. The nonwoven fabric structure 2 is formed into a single-layer structure by the water jet connector 240 and then fed to the dryer 250 and the calender 260.

[0101] After passing through the dryer 250 and the calender 260, the second fiber, including at least one side of the nonwoven structure 2, is deformed, and a surface with uniform roughness or different roughness depending on the location is formed in the single-layer nonwoven structure 2. The nonwoven structure 2 after passing through the calender 260 is fed to the winding machine 270 and formed into a curled state.

[0102] Based on the above description of the nonwoven fabric manufacturing apparatus 200 of this embodiment, a method for manufacturing a nonwoven fabric structure 2 using the above-described apparatus will be explained.

[0103] The method for manufacturing the nonwoven structure 2 includes the following steps (1) to (3): (1) forming a fiber mesh, the fiber mesh comprising a first fiber comprising one or more components selected from the group consisting of rayon, cellulose, polyester and polyamide, and a second fiber comprising a bicomponent fiber comprising synthetic resin components with different heat shrinkage rates; (2) performing a hydroentangling process on the fiber mesh formed in step (1) to form a nonwoven structure; and (3) drying the nonwoven structure formed in step (2) at 120 to 200°C.

[0104] (1) is a step of mixing the first fiber and the second fiber and feeding them into the nonwoven fabric manufacturing apparatus 200. Therefore, (1) includes the step of mixing the first fiber and the second fiber and the step of combing the mixed fibers 230 to form a fiber mesh. In step (1), the first fiber and the second fiber are mixed in a weight ratio of 1:1 to 3:2.

[0105] (2) The step is to spray a water jet by passing the stacked mesh through the water jet connector 240. The nozzles used for water jet spraying and the water spraying conditions are the same as described above.

[0106] (3) The step is to dry the nonwoven structure 2, which is to induce deformation of the bicomponent fibers included in the nonwoven structure 2 by passing through at least one of the dryer 250 and the calender 260.

[0107] Below, more specific embodiments of the present invention will be described based on the above-described embodiments. In this embodiment and comparative example, in the case of the nonwoven fabric structure to be impregnated, 10L of pure water at 25°C was placed in a water tank of size 600×600×300mm, and the nonwoven fabric structure was then completely immersed in the water and left for 1 hour. After drying in a constant temperature dryer at 50°C for 12 hours, the structure was tested.

[0108] Example 1. Double-layer nonwoven fabric structure

[0109] A first layer (basis weight 25 gsm) composed of 100% rayon fibers was manufactured by weaving and carding rayon fibers 2de, and a second layer (basis weight 35 gsm) composed of 100% bicomponent fibers 6de was manufactured by weaving and carding bicomponent fibers 6de. Regarding the bicomponent fibers, polypropylene was placed in the core position as the first component, and polyethylene was placed in the skin position as the second component. With the first layer stacked on one side of the second layer, water jets of 50 bar were sprayed onto both sides through a water jet binder with a nozzle orifice size of 0.12 mm and a nozzle spacing of 0.48 mm to perform water jet bonding. The bonded nonwoven fabric structure was then heated and dried at 130°C to manufacture a double-layer nonwoven fabric structure.

[0110] The surface of the second layer of the fabricated nonwoven structure was observed using a scanning electron microscope, and the image is as follows. Figure 6 As shown. The bicomponent fiber portion that makes up the second layer is melted and then hardened together with other fibers, thereby forming channels inside the second layer, which increases its size.

[0111] Example 2. Single-layer nonwoven fabric structure

[0112] A fiber mesh with a basis weight of 60 gsm was manufactured by mixing rayon fibers and bicomponent fibers, the same as those used in Example 1, at a weight ratio of 3:2. The fiber mesh was then water-bonded by spraying a 50 bar water jet onto both sides through a water jet bonder with a nozzle orifice size of 0.12 mm and a nozzle spacing of 0.48 mm. The bonded nonwoven structure was then heated and dried at 150°C to produce a single-layer nonwoven structure.

[0113] Comparative Example 1. Single-layer rayon nonwoven fabric

[0114] A single-layer fiber mesh (60 gsm basis weight) composed of 100% rayon fibers was prepared by weaving and carding rayon fibers 2de. The fiber mesh was then water-bonded under the same conditions as in the previous embodiment, and the bonded nonwoven structure was heated and dried at 150°C to produce a single-layer nonwoven structure.

[0115] Comparative Example 2. Single-layer nonwoven fabric

[0116] As Comparative Example 2, a dual-effect cleaning cloth product from 3M Company, which is sold on the market, was used. Comparative Example 2 is a nonwoven fabric structure with a single-layer structure (basis weight 125 gsm) made of microfiber.

[0117] Comparative Example 3. Single-layer nonwoven fabric

[0118] A fiber mesh with a basis weight of 60 gsm was manufactured by mixing rayon fibers and polyethylene terephthalate fibers in a weight ratio of 2:3, the same as in Comparative Example 1. The fiber mesh was then water-bonded under the same conditions as in the previous example, and the bonded nonwoven structure was heated and dried at 150°C to manufacture a single-layer nonwoven structure.

[0119] Comparative Example 4. Double-layer nonwoven fabric

[0120] A first layer (basis weight 30 gsm) was manufactured by mixing rayon fibers and polyethylene terephthalate fibers in a 2:3 weight ratio, the same as in Comparative Example 1, and carding the mixture. A second layer (basis weight 30 gsm) composed of 100% polypropylene fibers was manufactured by weaving and carding polypropylene fibers. With the first layer stacked on one side of the second layer, the mixture was water-bonded under the same conditions as in the above-described example. The bonded nonwoven fabric structure was then heated and dried at 150°C to manufacture a double-layer nonwoven fabric structure.

[0121] Comparative Example 5. Double-layer nonwoven fabric

[0122] A first layer (basis weight 25 gsm) composed of 100% rayon fibers was manufactured by weaving and carding rayon fibers 2de, and a second layer (basis weight 35 gsm) composed of 100% sizing agent was manufactured. The sizing agent was prepared by an air-laid process using air instead of water. With the first layer stacked on one side of the second layer, the nonwoven fabric structure was heated and dried at 150°C under the same conditions as in the above embodiment to manufacture a double-layer nonwoven fabric structure.

[0123] Experimental Example 1. Confirmation of the bulkiness of nonwoven fabric structures

[0124] The bulkiness of the nonwoven fabric structures manufactured according to Example 1 and Comparative Example 1 was confirmed. Fifteen sheets of nonwoven fabric structures of the same thickness prepared according to Example 1 and Comparative Example 1 were stacked on top of each other, and the degree of compression was compared by placing weights of the same weight on them.

[0125] like Figure 7As shown, the nonwoven fabric of Example 1 has a small degree of compression relative to the same weight, which is consistent with the fact that it can be compressed less within the nonwoven fabric structure of Example 1. Figure 6 The confirmed result is that the channel increases the size of the system.

[0126] Experimental Example 2. Confirmation of the roughness of nonwoven fabric structures

[0127] The surface roughness R along the centerline of the nonwoven structure prepared according to Example 1 and Comparative Example 1 was confirmed. a And the ten-point average unevenness R z The roughness of each structure was compared and analyzed. Various nonwoven fabric structures, each 5.78 mm in length and 5.78 mm in width, were prepared. Using the DSXP LFL3.6X as the objective lens in an Olympus DSX110-MSD, 3D depth was measured at a total magnification of 48x and the resulting composite was used to create a configuration file. Figure 8 Select any six regions P1 to P6 from the configuration file shown, and export the surface roughness R along the centerline. a And the ten-point average unevenness R z The results are shown in Table 1 below.

[0128] [Table 1]

[0129]

[0130] Under normal circumstances, the surface roughness R along the centerline of any surface in a nonwoven fabric structure is... a When the particle size is 50μm or larger, it exhibits excellent adsorption and capture effects for dust. With an adsorption layer (layer 1) and a capture layer (layer 2), the surface roughness R along the centerline of layers 1 and 2 is minimal. a The ratio is 1:1.1 to 1:1.5, and the ten-point average unevenness R of the first and second layers is... z When the ratio is 1:1.1 to 1:1.5, the adsorption and capture effects are excellent.

[0131] As can be confirmed from Table 1 above, the second layer of the nonwoven fabric structure in Embodiment 1 of the present invention has a centerline surface roughness R of an average of 53 μm or more. a The surface roughness R along the centerline of the first and second layers a Ratio and ten-point average unevenness R z The ratios ranged from 1:2 to 1:3. In contrast, Comparative Example 1, with its single-layer structure, failed to ensure sufficient centerline surface roughness R for dust adsorption and capture. a .

[0132] Experimental Example 3. Bending Length of Nonwoven Fabric Structures (length) confirmation

[0133] The bending lengths of the nonwoven structures prepared according to Example 1 and Comparative Example 1 were compared and analyzed. Five nonwoven structures with a horizontal length of 2.5 cm and a vertical width of 15 cm were prepared and dried in a constant temperature dryer at 50°C for 12 hours. Then, according to the cantilever beam method of ISO9073-7, they were pushed in the MD (machine direction: longitudinal) and CD (cross direction: transverse) directions until they reached an inclination of 41.5 degrees. The average bending length was measured and is shown in Table 2.

[0134] [Table 2]

[0135] Example 1 Comparative Example 1 MD direction 9.5cm 3.5cm CD direction 7.5cm 4.0cm average 8.5cm 3.75cm

[0136] The average bending length of the nonwoven fabric structure in Embodiment 1 of the present invention is 5 or more in the MD and CD directions, which provides excellent morphological safety for dust adsorption. In contrast, the average bending length of the nonwoven fabric structure in Comparative Example 1 is less than 5, which makes it less safe to wipe the nonwoven fabric structure when placed on the surface of the object.

[0137] Experimental Example 4. Dust Capture Rate Analysis of Nonwoven Fabric Structures

[0138] The dust capture rates of the nonwoven fabric structures prepared according to Example 1 and Comparative Examples 1 to 5 were compared and analyzed. First, each nonwoven fabric structure with a length of 10 cm and a width of 10 cm was prepared and allowed to absorb water, achieving a moisture content of 250% relative to the weight of the nonwoven fabric structure. As standard dust, 0.01 g of iron powder (iron powder, 200 mesh, average particle size 1.27 μm) was applied to the surface to be tested. The surface coated with the iron powder (surface area 10 cm long and 15 cm wide) was kept at a load of 0.5 kg relative to the wet nonwoven fabric structure, and the total weight of captured dust was measured by running a rubbing tester five times. The capture rate was then calculated. In the case of a double-layer nonwoven fabric structure, the softer surface (layer 1) was used as the applicable surface, and the results are shown in Table 3 below.

[0139] [Table 3]

[0140]

[0141] As can be confirmed from Table 3 above, a dust capture rate of over 90% was achieved in the nonwoven fabric structure of Example 1 of the present invention. In contrast, Comparative Example 1, with an application surface of 100% rayon fiber, showed no difference in composition from the application surface of Example 1, but its capture rate was only about 70%. Comparative Example 2, a commercially available microfiber nonwoven fabric, exhibited a capture rate of approximately 70%. This difference arises from the capture of adsorbed dust within the channels inside the second layer, which serves as the capture layer in Example 1.

[0142] In Comparative Example 3, simply mixing rayon and polyethylene terephthalate resulted in low adsorption capacity and a final dust capture rate of less than 50%.

[0143] In Comparative Examples 4 and 5, although the nonwoven fabric structure has a second layer, it cannot adequately provide the ability to capture adsorbed dust because it does not include bicomponent fibers and therefore cannot form channels inside.

[0144] The above experimental results demonstrate the dust-capturing effect of nonwoven structures that use a second layer of bi-component fibers as a trapping layer.

[0145] Additionally, images of the nonwoven fabric structures of Example 1 and Comparative Example 1 after dust was captured according to the above-described experiment, observed using a scanning electron microscope and an optical microscope, were compared. (Refer to...) Figure 9 In the nonwoven structures of Example 1 (a) and (b), a uniform trapping zone is formed from the rayon layer (layer 1) to the bicomponent fiber layer (layer 2), while in the nonwoven structures of Comparative Example 1 (c) and (d), a dust trapping zone is formed only relative to a portion of the rayon layer. These microscopic images of the various nonwoven structures support the roughness confirmed in Table 1 and the results in Table 3, as well as the importance of using bicomponent fibers to form the trapping layer for the trapping rate.

[0146] Experiment Example 5. Scrubbing Experiment Using Nonwoven Fabric Structures

[0147] A scrubbing test was conducted on the contaminant using a nonwoven fabric structure prepared according to Example 1 and Comparative Example 1. A wet nonwoven fabric was prepared using the same procedure as in Experimental Example 4. 2g of coffee was applied to the surface of the object in a circular pattern with a diameter of 0.5cm and allowed to dry, thus forming a stain. The stain was then examined under the same conditions as in Experimental Example 4 using a friction testing machine, with 30 cycles performed to determine both visual appearance and residual weight.

[0148] Figure 10Images are photographs taken of stains after 30 round trips using (a) the nonwoven fabric structure of Example 1 and (b) the nonwoven fabric structure of Comparative Example 1. The weight of the remaining stains was measured, and in the case of the nonwoven fabric structure of Example 1, more than 80% of the contamination was removed, while in the case of the nonwoven fabric structure of Comparative Example 1, less than 20% of the contamination was removed.

[0149] The experimental results indicate that the nonwoven fabric structure with a second layer containing dual-component fibers to increase surface roughness has a sufficient scrubbing effect on contaminants on the object surface.

[0150] The present invention is not limited to the embodiments described above, and a combination of the above embodiments or a combination of at least one of the above embodiments and known technologies can be implemented as another embodiment.

[0151] The present invention has been described in detail above through specific embodiments, but this is only for specific illustration of the present invention. The present invention is not limited thereto, and those skilled in the art can modify or improve it within the technical concept of the present invention.

[0152] Simple modifications and alterations to this invention are all included within the scope of this invention, and the specific scope of protection of this invention should be more clearly understood from the appended claims.

Claims

1. A nonwoven fabric structure, characterized by, comprises one or more components selected from the group consisting of rayon, cellulose, polyester, and polyamide; and a second layer including a second fiber that is a bi-component fiber including synthetic resin components having different thermal shrinkage rates from each other, wherein in the bi-component fiber, the synthetic resin components having different thermal shrinkage rates from each other are arranged in a sheath-core structure, and the core is arranged at an eccentric position of the sheath, the first layer is laminated to at least one surface of the second layer, and the first layer and the second layer are bonded by a hydroentangling process, the nonwoven fabric structure is configured to adsorb and capture dust. The second layer has a greater surface roughness than the first layer, and the center line surface irregularity R a The ratio is 1:1.1 to 1:5, and the center line surface irregularity R a The average roughness is a value obtained by dividing the sum of absolute values of distances from a hypothetical center line at each position of a cross section of a subject surface by the number of positions. The ten-point average unevenness R of the first layer and the second layer z The ratio is 1:1.1 to 1:5, the ten-point average unevenness R z The average value of the distance between the highest 5 peaks and the lowest 5 valleys of the cross section from the object surface with respect to the assumed center line 2. The nonwoven fabric structure according to claim 1, wherein in the hydroentangling process, water is sprayed from nozzles having holes with a diameter of 0.09 mm to 0.5 mm and arranged at an interval of 0.3 mm to 0.6 mm at a pressure of 40 bar to 60 bar.

3. The nonwoven fabric structure according to claim 1, wherein the bi-component fiber includes two or more synthetic resin components selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polytrimethylene terephthalate, poly-1,4-cyclohexylenedimethylene terephthalate, and nylon. comprises the following steps:

4. A method for producing a nonwoven fabric structure, characterized by (1) a step of forming a fiber mesh including a first fiber including one or more components selected from the group consisting of rayon, cellulose, polyester, and polyamide, and a second fiber that is a bi-component fiber including synthetic resin components having different thermal shrinkage rates from each other; (2) a step of forming a nonwoven fabric structure by performing a hydroentangling process on the fiber mesh formed in the (1) step; and (3) a step of drying the nonwoven fabric structure formed in the (2) step at 120°C to 200°C, wherein in the bi-component fiber, the synthetic resin components having different thermal shrinkage rates from each other are arranged in a sheath-core structure, and the core is arranged at an eccentric position of the sheath, the (1) step includes the following steps: carding the first fiber to form a first mesh; carding the second fiber to form a second mesh; and laminating the first mesh to at least one surface of the second mesh so that the first mesh forms a first layer, and the second mesh forms a second layer laminated on the first layer, the nonwoven fabric structure is configured to adsorb and capture dust. The second layer has a greater surface roughness than the first layer, and the center line surface irregularity R a The ratio is 1:1.1 to 1:5, and the center line surface irregularity R a The average roughness is a value obtained by dividing the sum of absolute values of distances from a hypothetical center line at each position of a cross section of a subject surface by the number of positions. The ten-point average unevenness R of the first layer and the second layer z The ratio is 1:1.1 to 1:5, the ten-point average unevenness R z The average value of the distance between the highest 5 peaks and the lowest 5 valleys of the cross section from the object surface relative to the assumed center line 5. The method of manufacturing a nonwoven fabric structure according to claim 4, wherein in the hydroentangling process, water is sprayed from nozzles having holes with a diameter of 0.09 mm to 0.5 mm and arranged at an interval of 0.3 mm to 0.6 mm at a pressure of 40 bar to 60 bar.

6. The method of manufacturing a nonwoven fabric structure according to claim 4, wherein the bi-component fiber includes two or more synthetic resin components selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polytrimethylene terephthalate, poly-1,4-cyclohexylenedimethylene terephthalate, and nylon. ​

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