Nonwoven fabric and method for manufacturing the same

Abstract

To provide a nonwoven fabric having a new design in which three areas having different patterns are regularly disposed on the whole of the nonwoven fabric by repeatedly and regularly forming two more areas at one of two entanglement parts extending in substantially one direction to constitute a stripe pattern.SOLUTION: A first entanglement part and a second entanglement part are disposed in stripe-like pattern on a nonwoven fabric. The second entanglement part at least includes a first area and a second area. In plan view, when a direction in which the first entanglement part and the second entanglement part continuously extend is an X direction and a direction orthogonal to the X direction is a Y direction, the first area and the second area are repeatedly and alternately disposed in the X direction. The first entanglement part, the first area, and the second area have different patterns from each other.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to a novel nonwoven fabric having a design in which at least two entangled portions are repeatedly and regularly formed to form a striped pattern, and in one of the two entangled portions, at least two regions are repeatedly and regularly formed in the direction in which the entangled portion extends, and to a method for manufacturing the same. [Background technology]

[0002] Nonwoven fabrics with striped patterns have been proposed, for example, in Patent Documents 1 and 2. In a nonwoven fabric with a striped pattern, two or more regions with different patterns are formed alternately or regularly, and the pattern of each region is determined by the dimensions and / or arrangement of the openings formed in that region. Since nonwoven fabrics with striped patterns can enhance the design and increase the added value of the nonwoven fabric, various striped patterns have been proposed. Furthermore, by adjusting the pattern of each region, the wiping performance of a nonwoven fabric with a striped pattern can be improved, for example, when used as a wiper.

[0003] Another document (Patent Document 3) proposes a patterned nonwoven fabric having low-density regions, first high-density regions, and second high-density regions, wherein multiple low-density regions aggregate to form a single island-like portion, and within one island-like portion, a second high-density region is formed at least between low-density regions, and the first high-density region is formed between the island-like portions. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2000-45161 [Patent Document 2] Japanese Patent Publication No. 2009-287158 [Patent Document 3] International Release 2017 / 164195 Brochure [Overview of the project] [Problems that the invention aims to solve]

[0005] This disclosure provides a nonwoven fabric having a novel design, in which two additional regions are repeatedly and regularly formed in one of two intertwined portions that extend substantially in one direction and constitute a striped pattern, so that three different patterned portions are regularly arranged throughout the nonwoven fabric. [Means for solving the problem]

[0006] This disclosure, in the first abstract, describes a nonwoven fabric in which a first entanglement portion and a second entanglement portion are arranged in a striped pattern, The second confluence includes at least a first region and a second region, In a plan view, when the direction in which the first and second entangled portions extend continuously is defined as the X direction, and the direction perpendicular to the X direction is defined as the Y direction, the first region and the second region are repeatedly and alternately arranged in the X direction. The first entangled portion, the first region, and the second region have different patterns from each other. We provide nonwoven fabric.

[0007] In the summary in Section 2 of this disclosure, To create a fiber web, The fiber web is placed on a support, and the fiber web is subjected to entanglement treatment by a high-pressure fluid flow. A method for producing a nonwoven fabric containing, The support has at least two types of woven structures A and B, In the support, the woven structure A and the woven structure B are band-shaped portions that extend along the direction in which the weft threads extend, and the woven structure A and the woven structure B are regularly and repeatedly formed along the direction in which the warp threads extend. The entanglement treatment of the fiber web placed on the support by a high-pressure fluid flow is carried out by injecting a high-pressure fluid flow from two or more consecutive orifices of a nozzle into the fiber web along the direction in which the weft yarns of the support extend, such that portions where the high-pressure fluid flow is injected into the fiber web and portions where the high-pressure fluid flow is not injected into the fiber web are alternately positioned. Provided is a method for manufacturing a non-woven fabric.

Effect of the Invention

[0008] The non-woven fabric of the present disclosure has a unique design property that appears to be both a stripe pattern and a grid pattern. In one of the two entanglement portions that extend substantially in one direction and form a stripe pattern, two regions are repeatedly and regularly formed, and three different patterned portions are regularly arranged throughout the non-woven fabric. This non-woven fabric is suitable for applications where appearance is emphasized (for example, surface materials for cosmetics and absorbent articles). Further, for example, when the non-woven fabric of the present disclosure is used as a wiper for wiping dirt off a human body or an article, particularly by selecting the patterns of the first region and the second region, the dirt can be wiped off better.

Brief Description of the Drawings

[0009] [Figure 1] It is an organizational diagram of an example of a support used in manufacturing the non-woven fabric of the present embodiment. [Figure 2] It is an organizational diagram of an example of a support used in manufacturing the non-woven fabric of the present embodiment. [Figure 3] It is a photograph showing the surface of the non-woven fabric manufactured in Example 1 corresponding to an example of the non-woven fabric manufactured using the support of FIG. 1. [Figure 4] It is a photograph showing the surface of the non-woven fabric manufactured in Example 2 corresponding to an example of the non-woven fabric manufactured using the support of FIG. 2. [Figure 5] It is an organizational diagram of an example of a support used in manufacturing the non-woven fabric of the present embodiment. [Figure 6] It is a photograph showing the surface of the non-woven fabric manufactured in Example 3 corresponding to an example of the non-woven fabric manufactured using the support of FIG. 5. [Figure 7]This is a plan view showing the acute angle 'a' between the diagonal lines of the diagonal pattern and the Y direction when the first region formed in the second confluence is a diagonal pattern. [Figure 8] This is a plan view showing the distance Da between the centers of adjacent openings when the first region formed in the second confluence has a diagonal pattern and openings are formed in the diagonal lines. [Figure 9] This is a plan view showing the distance Db between the centers of adjacent low-density regions when the second region formed in the second confluence is a pattern in which low-density regions are arranged in a staggered pattern. [Figure 10] This is a plan view showing a meandering first entanglement portion in an example of the nonwoven fabric of this embodiment. [Figure 11] This is a photograph showing the surface of the nonwoven fabric produced in Example 4. [Figure 12] This is a photograph showing the surface of the nonwoven fabric produced in Example 5. [Figure 13] This is a photograph showing the surface of the nonwoven fabric produced in Example 6. [Figure 14] This is a photograph showing the surface of the nonwoven fabric produced in Example 7. [Figure 15] This is a photograph showing the surface of the nonwoven fabric produced in Example 8. [Figure 16] This is a photograph showing the surface of the nonwoven fabric produced in Example 9. [Figure 17] This is a photograph showing the surface of the nonwoven fabric produced in Example 10. [Figure 18] This is a photograph showing the surface of the nonwoven fabric produced in Example 11. [Figure 19] This is a photograph showing the surface of the nonwoven fabric produced in Example 12. [Figure 20] This is a side cross-sectional photograph showing a method for determining the height difference between the surface of woven structure A and the surface of woven structure B in an example of a support used in the manufacture of the nonwoven fabric of this embodiment. [Figure 21] This is a side cross-sectional photograph showing a method for determining the height difference between the surface of woven structure A and the surface of woven structure B in an example of a support used in the manufacture of the nonwoven fabric of this embodiment. [Figure 22]This is a side cross-sectional photograph showing a method for determining the height difference between the surface of woven structure A and the surface of woven structure B in an example of a support used in the manufacture of the nonwoven fabric of this embodiment. [Modes for carrying out the invention]

[0010] (Background leading to this embodiment) In the nonwoven fabrics disclosed in the above-mentioned Patent Documents 1 and 2, the rows or patterned areas constituting the striped pattern extend in the MD direction (longitudinal direction) of the nonwoven fabric, and two or more regions of different patterns are regularly arranged along the CD direction (transverse direction) (hereinafter, such striped patterns will be conveniently referred to as "vertical stripes"). Vertical stripes are formed, for example, when manufacturing nonwoven fabrics by the water entanglement method, by regularly changing the water jet injection conditions in the CD direction. For example, vertical stripes can be formed by blocking the orifice in the region corresponding to one of the rows of stripes in the nozzle that injects the water jet. Alternatively, vertical stripes can be formed by placing a plate with equally spaced openings between the nozzle and the fiber web, creating areas where the water jet that has passed through the openings hits and areas where the water jet is blocked by the plate and does not hit. Alternatively, vertical stripes can also be formed in the support that transports the fiber web during the water entanglement process by regularly changing the structure of the support (for example, the weave structure of the support) in a direction perpendicular to the direction of travel. Furthermore, according to Patent Document 3, by allowing island-like portions to exist independently, it is possible to obtain, for example, a nonwoven fabric with a grid pattern.

[0011] The inventors conducted various studies to obtain patterns that could not be obtained with conventional nonwoven fabrics. As a result, by using a nozzle or plate when forming the vertical stripes and using a specific support during water flow entanglement, they obtained a nonwoven fabric with a unique design in which three different parts of the pattern are regularly arranged, appearing as stripes, a grid pattern, or even a ladder-like pattern. The method for manufacturing the nonwoven fabric of this embodiment will be described first, followed by a description of the structure of the nonwoven fabric of this embodiment.

[0012] (Embodiment 1: Method for manufacturing nonwoven fabric) The method for manufacturing the nonwoven fabric of this embodiment is: To create a fiber web, The fiber web is placed on a support, and the fiber web is subjected to entanglement treatment by a high-pressure fluid flow. A method for producing a nonwoven fabric containing, The support has at least two types of woven structures A and B, In the support, the woven structure A and the woven structure B are band-shaped portions that extend along the direction in which the weft threads extend, and the woven structure A and the woven structure B are regularly and repeatedly formed along the warp direction. The entanglement treatment of the fiber web placed on the support by a high-pressure fluid flow is carried out by injecting the high-pressure fluid flow along the direction in which the weft threads extend on the support, such that portions of the fiber web are alternately positioned where a high-pressure fluid flow is injected from two or more consecutive orifices of a nozzle, and portions where a high-pressure fluid flow is not injected. This is a method for manufacturing nonwoven fabrics.

[0013] This manufacturing method corresponds to a method in which fibers are entangled and integrated by spraying a high-pressure fluid stream onto a fiber web. The high-pressure fluid is, for example, a high-pressure gas such as compressed air, and a high-pressure liquid such as high-pressure water. In the manufacture of nonwoven fabrics, a water flow entanglement treatment using high-pressure water as the high-pressure fluid is often used, and in this embodiment as well, a water flow entanglement treatment is preferably used from the standpoint of ease of implementation. Below, a manufacturing method using a high-pressure water stream (hereinafter simply referred to as "water stream") as the high-pressure fluid stream will be described.

[0014] In this manufacturing method, a water flow entanglement treatment is partially performed on the fiber web while it is placed on a specific support, such that areas where a high-pressure fluid flow is injected from two or more consecutive orifices of a nozzle onto the fiber web and areas where a high-pressure fluid flow is not injected onto the fiber web are alternately positioned along the direction in which the weft threads of the support extend (hereinafter referred to as "pattern formation entanglement treatment"). In the pattern formation entanglement treatment, areas where the water flow does not hit and areas where the water flow hits are alternately arranged along the CD direction of the nonwoven fabric. Furthermore, in this manufacturing method, by performing the pattern formation entanglement treatment using a specific support, the areas where the water flow hits can be made to have two different pattern regions, making it possible to form three different pattern regions (a region where the water flow is not injected, and a first region and a second region formed in the area where the water flow is injected) in the resulting nonwoven fabric.

[0015] In this embodiment, it is desirable to subject the entire fiber web to a water flow entanglement treatment (hereinafter referred to as "overall entanglement treatment") before the pattern formation entanglement treatment. The overall entanglement treatment is carried out under the same treatment conditions throughout the entire fiber web. Furthermore, the overall entanglement treatment may be carried out in such a way that the fiber web after the entanglement treatment does not have a pattern, i.e., becomes patternless. By performing the overall entanglement treatment, the fibers are entangled to a certain extent in advance, forming a portion that will become the first entangled portion in the resulting nonwoven fabric, and then in the subsequent pattern formation entanglement treatment, a second entangled portion can be formed as a portion different from the first entangled portion.

[0016] The overall entanglement process is carried out by placing the fiber web on a support and spraying it with a columnar stream of water. For example, the support is preferably a plain weave support with a mesh size of 80 or more and 100 or less. With such a support, it is possible to entangle the fibers of the fiber web without forming a pattern on the fiber web, and to achieve a good texture.

[0017] The fiber web can be manufactured by known methods. The form of the fiber web may be selected from, for example, card webs such as parallel webs, cross webs, semi-random webs and random webs, as well as air-lay webs and wet-machine webs. In this embodiment, a card web is preferably used because it is easy to obtain thickness and create irregularities.

[0018] The overall entanglement treatment may be performed by spraying a water stream at a pressure of 1 MPa to 15 MPa onto the front and back surfaces of the fiber web 1 to 5 times each, from a nozzle equipped with orifices with a pore diameter of 0.05 mm or more and 0.5 mm or less, spaced at intervals of 0.3 mm or more and 1.5 mm or less. The water pressure is preferably 1 MPa to 10 MPa, and more preferably 1 MPa to 7 MPa.

[0019] In the pattern-forming entanglement process, a support is used which is a support formed by weaving warp and weft threads, and which includes at least two types of weave structures A and B, wherein weave structures A and B are strip-shaped portions that extend along the direction in which the weft threads extend (generally the direction perpendicular to the direction in which the support advances during nonwoven fabric manufacturing, hereinafter also referred to as the "CD direction"), and weave structures A and B are regularly and repeatedly formed along the direction in which the warp threads extend (generally the direction in which the support advances during nonwoven fabric manufacturing, hereinafter also referred to as the "MD direction"), and a single support (hereinafter conveniently referred to as the "pattern-forming support") is used. In the pattern-forming support, weave structures A and B extend over the entire width of the support in the CD direction, or over the entire width of the nonwoven fabric to be manufactured in the CD direction. By spraying a stream of water onto the fiber web on this support, regions having patterns (including no patterns) determined by each weave structure are formed by rearranging the fibers.

[0020] In the pattern-forming support, for example, weave structures A and B are arranged in the order ABAB... along the direction in which the warp threads extend (MD direction). Therefore, if the regions formed in the nonwoven fabric by weave structures A and B of this support are called the first region and the second region, then in the nonwoven fabric, two regions are formed in the order of first region-second region-first region-second region... along the MD direction, and a transverse stripe pattern (i.e., transverse stripes) is formed as the first and second regions extend along the CD direction, which is perpendicular to the MD direction. Furthermore, it is also possible to add weave structure C and arrange it in the order ABCABC... along the MD direction. Examples of weave structures include plain weave, twill weave, satin weave, and herringbone weave. For example, weave structure A may be a 2 / 2 twill weave, weave structure B a plain weave, and weave structure C a 3 / 1 twill weave. With a support incorporating three or more weave structures, a transverse stripe pattern can be formed in the resulting nonwoven fabric in a number of regions with different surface properties. Furthermore, the exemplified weave structures may be irregular, such as a loose twill weave. By using an irregular structure, the parts where the warp threads pass over the weft threads and float are dispersed, and the openings or depressions formed due to these floating warp threads are dispersed, which can impart a unique design to the nonwoven fabric.

[0021] In this embodiment, when a water stream is sprayed with a fiber web placed on a pattern-forming support, a nozzle having a group of orifices consisting of one or more orifices arranged at predetermined intervals may be used, or a member (hereinafter simply referred to as a "perforated member") having a row of holes arranged perpendicular to the direction of travel of the support, and which does not allow high-pressure fluid to pass through except the holes, may be placed between the fiber web and the nozzle to form a second entanglement. As a result, during the water stream entanglement process, areas on the fiber web that are not hit by the water stream are continuously formed in the MD direction, and these areas are formed at intervals in the CD direction. The areas that were not hit by the water stream and the areas where the fibers were rearranged by the water stream become the first entanglement and second entanglement in the resulting nonwoven fabric, and the first and second entanglement are arranged alternately in the CD direction to form a striped pattern.

[0022] More specifically, when using a nozzle in which orifice groups are provided at predetermined intervals, only the water flow ejected from the orifice groups acts on the web. Therefore, a high-pressure water flow with the energy necessary to form a pattern corresponding to the pattern-forming support acts only on the portion of the web corresponding to the orifice group. In this nozzle, the orifice groups are provided over a section corresponding to the width of the second entanglement. The spacing of the orifice groups corresponds to the width of the first entanglement. Such a nozzle may be one in which the orifices are plugged in the section corresponding to the first entanglement, in a nozzle designed to apply water flow over the entire surface, as described in relation to the overall entanglement process. A single orifice group preferably consists of two or more orifices. When there are two or more orifices, a pattern corresponding to the pattern-forming support can be formed more clearly in the second entanglement. The spacing between adjacent orifices in an orifice group may be, for example, 0.2 mm to 1.5 mm.

[0023] In the method of forming a second entanglement using a perforated member, only the water flow passing through the holes acts on the web. Therefore, a high-pressure water flow with the energy necessary to form a pattern corresponding to the pattern-forming support acts only on the portion of the web corresponding to the hole. The perforated member is not particularly limited as long as it has multiple holes. For example, the material may be synthetic resin or metal. Also, the shape may be plate-shaped or roll-shaped, etc., and can be appropriately selected according to the water flow entanglement treatment apparatus.

[0024] Multiple holes in the perforated member are formed along a direction perpendicular to the direction of travel of the support. Each hole has a dimension of, for example, 2 mm or more in the direction perpendicular to the direction of travel of the support, and may have a dimension of 3 mm to 50 mm, and more particularly 5 mm to 30 mm. When forming a second entanglement with a different width, holes of different dimensions are formed in a single perforated member according to the width of the second entanglement to be obtained. The spacing between adjacent holes in the perforated member may be, for example, 2 mm or more, may be particularly 3 mm to 50 mm, and more particularly 5 mm to 30 mm. The spacing between adjacent holes determines the width of the first entanglement, so it is appropriately selected according to the width of the first entanglement to be obtained. The shape of the holes is not particularly limited and may be, for example, circular, semicircular, elliptical, polygonal (triangle or quadrilateral), star polygon, cross-shaped, or slit-shaped (straight or curved).

[0025] When using perforated members, the nozzle is not particularly limited and may be the same as that described in relation to the overall entanglement process. The distance between the perforated member and the nozzle may be, for example, 1 mm or more. If the distance between the perforated member and the nozzle is less than 1 mm, the perforated member and the nozzle may come into contact, and one or both may be damaged. On the other hand, the distance between the perforated member and the nozzle may be, for example, 30 mm or less. If the distance between the perforated member and the orifice exceeds 30 mm, the energy of the water flow may decrease, and the pattern may not be formed properly. The distance between the perforated member and the fiber web may be, for example, 5 mm to 50 mm. If the distance between the perforated member and the fiber web exceeds 50 mm, the energy of the water flow may decrease, and the pattern may not be formed properly.

[0026] The range of water pressure that may be used during the pattern formation entanglement treatment is as described in relation to the overall entanglement treatment. Pattern formation entanglement treatment is usually performed by spraying a stream of water onto one side of the fiber web after the overall entanglement treatment. The pressure during the pattern formation entanglement treatment may be 1 MPa to 15 MPa, and more particularly 2 MPa to 10 MPa.

[0027] In the pattern-forming entanglement process, by fixing the position of the nozzle or perforated member and advancing the pattern-forming support along the longitudinal or transverse direction (usually the longitudinal direction) of the fiber web, a nonwoven fabric is obtained in which a plurality of first entanglements and a plurality of second entanglements extend linearly in the longitudinal or transverse direction of the nonwoven fabric.

[0028] In the pattern-forming entanglement process, vibrating a nozzle or perforated member and advancing the pattern-forming support along the longitudinal or transverse direction (usually the longitudinal direction) of the fiber web yields a nonwoven fabric with a meandering configuration of first and second entanglements. Here, "vibration" means moving the nozzle or perforated member back and forth along a certain direction. "Vibration" includes not only moving back and forth in a straight line, but also moving back and forth along an elliptical orbit with a certain direction as its major axis.

[0029] The vibration direction of the nozzle or perforated member may be appropriately selected from the longitudinal (MD) direction, transverse (CD) direction, and diagonal direction of the web. Here, "diagonal direction" means a direction that forms an angle with the longitudinal or transverse direction along the surface direction of the web, in the range of 0 degrees to less than 90 degrees. Considering ease of manufacturing, the vibration direction is preferably the transverse direction, or a direction that forms an angle with the transverse direction in the range of 0 degrees to 45 degrees or less.

[0030] The amplitude of the vibration of the nozzle or perforated member will be approximately the same as the amplitude of the first entanglement (the amplitude will be described later) in the resulting nonwoven fabric. Therefore, the amplitude of the vibration of the nozzle or perforated member is determined according to the amplitude of the first entanglement to be obtained. The length of the meandering per period of the first entanglement is determined by the vibration velocity of the nozzle or perforated member and the advancement velocity of the pattern-forming support. Therefore, the vibration velocity of the nozzle or perforated member is determined according to the length of the meandering per period of the first entanglement to be obtained, taking into account the advancement velocity of the pattern-forming support.

[0031] The vibration speed of the perforated member can be increased to approximately 100 m / min. By increasing the vibration speed of the perforated member, the difference between the width X at the turning points of the entanglement sections, such as the first and second entanglement sections, and the width Y at other points can be increased.

[0032] In the pattern-forming support used in this embodiment, the diameters of the weft yarn a constituting the weave structure A and the weft yarn b constituting the weave structure B are different, and the weft yarns a and b may be adjacent to each other at the boundary between weave structure A and weave structure B. Furthermore, in the pattern-forming support, the surface of weave structure A may be located 0.1 mm to 3.0 mm higher than the surface of weave structure B, particularly 0.5 mm to 2.5 mm higher, and more particularly 0.8 mm to 2.0 mm higher. A support having either or both of these configurations can be used to form a narrow third region at the boundary between the first and second regions.

[0033] The difference in height between the surface of weave structure A and the surface of weave structure B is determined by observing the side or cross-section of the support in the MD direction, and taking the difference between the highest point of weave structure A (usually the point where the warp threads are floating at the boundary between weave structure A and weave structure B) and the highest point of weave structure B. When cutting the support to observe the cross-section, the highest point of the weave may not be easily visible in the cross-section depending on the cutting location. In this case, the highest point is determined by finding the location further back than the photographed cross-section, or by cutting the support at several different locations and observing the different cross-sections to determine the distance between the highest points of each tissue. However, when the surface of the tissue is photographed obliquely on the far side of the cross-section, the warp and weft threads located on the far side should be ignored when determining the surface height. Depending on the weave structure of the support, the highest point may be the weft thread or the warp thread.

[0034] Figures 20 to 22 show a method for determining the height difference between the surface of woven fabric A and the surface of woven fabric B from the side cross-section of the support. Figure 20 corresponds to the support of the woven fabric shown in Figure 1, which will be described later. In Figure 20, a line LB is drawn that passes through the highest point on the surface of woven fabric B and is parallel to the surface of the stand on which the support is placed, and a line LA is drawn that passes through the highest point on the surface of woven fabric A (the highest point on the surface of the weft yarn indicated by the symbol a1) and is parallel to the surface of the stand on which the support is placed. The distance between LA and LB (the distance in the direction perpendicular to the surface of the stand on which the support is placed) corresponds to the height difference between the surface of woven fabric A and the surface of woven fabric B.

[0035] Figure 21 corresponds to the support structure of the woven fabric shown in Figure 2, which will be described later, and Figure 22 corresponds to the support structure of the woven fabric shown in Figure 5, which will be described later. Similar to Figure 20, in these figures, LB is a line that passes through the highest point on the surface of woven fabric B and is parallel to the surface of the stand on which the support structure is placed, and LA is a line that passes through the highest point on the surface of woven fabric A (the surface of the warp thread at the highest point) and is parallel to the surface of the stand on which the support structure is placed. In Figure 21, the surface of woven fabric B is obliquely shown on the far side of the side cross-section, but this is ignored when determining LB.

[0036] In the support structure described above, a step is formed at the boundary between the two structures, and / or a wider gap is formed between the weft threads than in other parts. At this step or gap, the fiber web is subjected to the action of the water flow under different conditions than the fiber web on weave structures A and B, and / or is affected by suction during the water flow entanglement treatment. As a result, a third region with a different pattern from both the first and second regions may be formed as a narrow region.

[0037] Furthermore, at the boundary between weave structure A and weave structure B, due to reasons such as changes in the diameter of the weft threads and changes in the weave structure, the state of the warp threads floating differs from the floating warp threads in weave structure A and weave structure B, forming a section (called a "knuckle") that is thought to create an opening in the third region of the nonwoven fabric obtained by this knuckle. In addition, at the boundary, the weft threads may behave differently from other parts, for example, by meandering, and this is also thought to be a factor in the formation of the third region and / or determine the pattern in the third region.

[0038] In this embodiment, the pattern-forming support may be one in which twill weave sections as weave structure A and plain weave sections as weave structure B are alternately formed along the direction of weaving. In such a support, the diameter of weft yarn a may be larger than the diameter of weft yarn b. Below, an example of such a pattern-forming support will be described with reference to its weave structure.

[0039] The twill weave section, which is weft structure A, may be a weft twill weave structure in which, for example, the number of floating weft threads is 2 or more and the number of floating warp threads is 1. Figure 1 is a structural diagram of a support structure in which weft structure A, which is 1 / 7 of the weft twill weave section, and weft structure B, which is the plain weave section, are formed. Figure 2 is a structural diagram of a support structure in which weft structure A, which is 1 / 3 of the weft twill weave section, and weft structure B, which is the plain weave section, are formed. In the structural diagrams, the colored parts are warp threads floating above the weft threads. Note that Figures 1 and 2, and Figure 5 described later, schematically show the repetition of weft structure A and weft structure B, and the number of warp and weft threads etc. that constitute each structure shown in the drawings are illustrative. Also, examples of nonwoven fabrics manufactured from the supports shown in these drawings are shown in Figures 3, 4 and 6, but the number of warp and weft threads etc. in each region of the support actually used in the manufacture of these nonwoven fabrics may differ from those shown.

[0040] In the pattern-forming support in Figure 1, knuckle a is formed at the boundary between the two tissues by the floating portion of the warp threads. In Figure 1, knuckle a is formed when the warp threads float above weft threads a and b. In other areas, the warp threads float above a single weft thread, and it can be seen that knuckle a is formed by the floating of the warp threads in a different state than in other areas. After performing an overall entanglement treatment, a fiber web is placed on this pattern-forming support, and a pattern-forming entanglement treatment is performed using a nozzle equipped with orifices at predetermined intervals to produce a nonwoven fabric having a pattern as shown in Figure 3. The nonwoven fabric in Figure 3 has a first entangled area that was not exposed to the water flow during the pattern-forming entanglement treatment, and a second entangled area formed by the pattern-forming entanglement treatment. The second entangled area has a first region having a diagonal pattern provided by the twill weave (weave structure A), and a second region formed from the plain weave (weave structure B) with openings or recesses arranged in a staggered pattern. In addition, in the second entangled area, a third region is formed, which is a stitch-like region with relatively clearly formed openings, regularly arranged in the order of first region → third region → second region. The structure of the nonwoven fabric will be described in detail in Embodiment 2.

[0041] In the second entanglement region of the nonwoven fabric in Figure 3, a third region is formed only at the boundary between one second region and the first region on the lower side of the figure. The third region is formed during the pattern-forming entanglement process when a water stream is sprayed onto the fiber web while the support is advanced, with the water stream sequentially sprayed from the fiber web at a lower position (woven structure B) to the fiber web at a higher position (woven structure A). As the process progresses, the fiber web extending from a lower position to a higher position is thought to be more susceptible to the effects of the water stream, making it easier to reflect knuckles and other features at the step in the nonwoven fabric. On the other hand, in the other step where the water stream is sprayed in order from the fiber web at a higher position (woven structure A) to the fiber web at a lower position (woven structure B), some of the water stream "flows down" over the fiber web extending from a higher position to a lower position, and is not firmly received by the fiber web, resulting in a weaker degree of entanglement. As a result, openings and / or recesses are less likely to form, a third region with a distinct pattern is not formed, and a nonwoven fabric like the one shown in Figure 3 is obtained.

[0042] In the pattern-forming support shown in Figure 2, knuckle a is a warp thread floating above a single weft thread. Knuckle a is the portion where the warp thread passes over a thicker weft thread a, but before and after the direction of knuckle a's progression, the warp thread passes over a thinner weft thread b. Therefore, the arrangement of weft threads (especially the spacing between weft threads) near knuckle a differs from the arrangement of weft threads in other tissues, and it is thought that this is why knuckle a forms a characteristic opening and / or opening in the third region of the second confluence.

[0043] After an overall entanglement treatment, a fiber web is placed on the support shown in Figure 2, and a pattern-forming entanglement treatment is performed using a nozzle with orifices arranged at predetermined intervals to produce a nonwoven fabric having a pattern as shown in Figure 4. The nonwoven fabric in Figure 4 has a first entanglement section formed by the overall entanglement treatment and a second entanglement section formed by the pattern-forming entanglement treatment. The second entanglement section has a first region in which openings provided by the twill weave section (weave structure A) are arranged regularly, and a second region in which openings or recesses formed by the plain weave section (weave structure B) are arranged in a staggered pattern. In addition, in the second entanglement section, a third region is formed, which is a stitch-like region with clearly formed openings, regularly arranged in the order of first region → third region → second region from top to bottom in the figure. The structure of the nonwoven fabric will be described in detail in Embodiment 2. In the first region of the second entanglement section of the nonwoven fabric shown in Figure 4, relatively clear openings are formed at positions corresponding to the parts where the warp threads are floating in weave structure A. This is thought to be because the weave structure A is a 1 / 3 weft twill weave, and the curvature in the floating warp threads is stronger than, for example, that in the weave structure A of the support in Figure 1, resulting in more pronounced bulges in the floating areas. Furthermore, it can be considered that there are areas where the warp threads are floating diagonally adjacent to the floating warp threads, and these together form a large convex area. In addition, in the weave structure A of the support in Figure 2, continuous diagonal lines are not formed by the floating warp threads, so diagonal patterns are less likely to form in the first region of the resulting nonwoven fabric.

[0044] The nonwoven fabric shown in Figure 4 also has a structure in which the first region → third region → second region is repeatedly formed in the second entanglement region, and the third region is formed only at the boundary with the first region on the lower side of the figure when viewed from one second region. The reason for the formation of the third region in this way is thought to be the same as the reason explained with reference to Figure 3 above.

[0045] The weave structure A of the pattern-forming support is not limited to having 1 warp thread floating, but may be a twill weave section with 2 or more warp thread floating. The upper limit of the warp thread floating may be, for example, 16, and particularly 10. In this case, the number of weft thread floating may be, for example, 2 or more and 16 or less, and particularly 2 or more and 10 or less. For example, the pattern-forming support may be a structure A which is a 2 / 2 twill weave section and a structure B which is a plain weave section, as shown in the structure diagram of Figure 5.

[0046] In twill weave sections where the number of floating warp threads is two or more, a characteristic knuckle is formed at the boundary with the plain weave section. As shown in Figure 5, at one boundary of the twill weave section to the plain weave section, a knuckle N1 is formed floating on three or more consecutive weft threads, including weft threads a and b. Because this knuckle N1 is elongated in the vertical direction, it tends to form a vertically elongated opening at the boundary between the first and second regions.

[0047] Furthermore, in the pattern-forming support shown in Figure 5, a knuckle N2 is formed at the boundary opposite to the boundary on the side where knuckle N1 is formed, where the warp thread floats over two or more consecutive weft threads including weft threads a and b. Adjacent to one side of knuckle N2, a knuckle N3 is formed where the warp thread floats over two or more consecutive weft threads. Since knuckles N2 and N3 are formed in close proximity, in the resulting nonwoven fabric, a region is formed between the first region and the second region where two adjacent openings or two openings are connected to form one larger opening.

[0048] As shown in the support in Figure 5, if the number of warp floats (the number of weft threads that are continuously positioned above a warp thread) and the number of weft floats (the number of warp threads that are continuously positioned above a weft thread) are the same in the woven structure, then the number of warp and weft floats will be the same on both main surfaces. Such a support makes it possible to manufacture nonwoven fabrics with substantially the same pattern, regardless of which of the two main surfaces is used as the surface on which the fiber web is placed. However, in the twill weave section, the direction of the diagonal lines formed by the warp threads is mirror-image symmetrical between the two main surfaces, and the direction of the diagonal lines formed in the resulting nonwoven fabric will be opposite.

[0049] Figure 6 shows an example of a nonwoven fabric produced by performing a pattern-forming entanglement treatment using a nozzle equipped with orifices at predetermined intervals, after performing an overall entanglement treatment, by placing a fiber web on the support shown in Figure 5. The nonwoven fabric in Figure 6 was produced by performing a water flow entanglement treatment so that the boundary where the knuckle N1 is formed is sprayed into the water flow first during the pattern-forming entanglement treatment, that is, with the arrow shown on the right side of the microstructure diagram in Figure 5 as the direction of travel. In the nonwoven fabric in Figure 6, the first region of the second entanglement area has a diagonal pattern in which diagonal lines with openings and diagonal lines without openings are arranged alternately. The openings correspond to the parts where the warp threads are floating in the twill weave section in Figure 5, and since the warp threads floating on two weft threads are adjacent in the twill weave section, relatively clear openings are formed in the nonwoven fabric.

[0050] The second entanglement region of the nonwoven fabric in Figure 6 has a third region formed corresponding to the boundary containing knuckle N1, and a fourth region formed corresponding to the boundary containing knuckles N2 and N3. The four regions are repeatedly formed in the order of first region → third region → second region → fourth region. Both the third and fourth regions have different patterns from the first and second regions, emphasizing the boundary between the first and second regions. Because knuckle N1 is long and floating above three weft threads, it makes the opening of the third region larger than the opening formed in the first region, and the direction of the diagonal lines formed in the opening of the first region appears to be changed in the third region. Knuckle N2 passes over the weft threads constituting weft structure A and weft structure B at the boundary between weft structures A and B, so that the warp threads reach a lower position on the weft structure B side before passing under the weft threads of weft structure B. This is thought to be what makes the pattern of the fourth region different from the other regions. Furthermore, at the boundary between weave structure A and weave structure B, the spacing of the weft threads tends to be wider than that in weave structure A and weave structure B, which is also thought to be what makes the patterns in the third and fourth regions different from those in the other regions.

[0051] In the nonwoven fabric of Figure 6, regions with patterns different from the first and second regions are formed at the upper and lower boundaries of the figure, as viewed from the second region formed on the second support. Knuckles N2 and N3 are relatively large because the warp threads are floating above two weft threads. Therefore, even when water flow acts sequentially on the fiber web spanning from a high position to a low position, the knuckles are more susceptible to influence, and it is thought that a clearer pattern is formed compared to the supports in Figures 1 and 2 (where the number of floating warp threads is 1 in the knuckles at the boundary of the woven structure on the rear side in the direction of travel).

[0052] The illustrated pattern-forming support is an example, and the weave structures A and B may be other than those shown. Furthermore, the width in the MD direction of each weave structure, the diameters of the wefts a and b, and the diameter of the warp threads are appropriately selected so as to obtain the desired striped or ladder-like pattern and the desired patterns in the first and second regions at the second entanglement.

[0053] In the pattern-forming support, the dimensions in the MD direction of woven structures A and B determine the dimensions in the MD direction of the first and second regions formed in the second entanglement in the resulting nonwoven fabric (i.e., the dimensions in the X direction when the direction in which the first and second entanglement extends is defined as the X direction). In this embodiment, the dimensions in the MD direction of woven structure A may be 2 mm or more and 200 mm or less, particularly 3 mm or more and 100 mm or less, more particularly 5 mm or more and 50 mm or less, even more particularly 7 mm or more and 30 mm or less, and even more particularly 10 mm or more and 25 mm or less. Similarly, the dimensions in the MD direction of woven structure B may be 2 mm or more and 200 mm or less, particularly 3 mm or more and 100 mm or less, more particularly 5 mm or more and 50 mm or less, even more particularly 7 mm or more and 30 mm or less, and even more particularly 10 mm or more and 25 mm or less. The dimensions in the MD direction of woven structure A may be the same as or different from the dimensions in the MD direction of woven structure B. Furthermore, a single support may contain multiple woven structures A with different dimensions in the MD direction, and / or multiple woven structures B with different dimensions in the MD direction.

[0054] The warp and weft threads constituting the pattern-forming support may be, for example, filaments with a diameter of 0.3 mm or more and 1.2 mm or less. The diameter of the weft thread may be, for example, 0.5 mm or more and 1.2 mm or less, particularly 0.9 mm or more and 1.0 mm or less, and more particularly 0.65 mm or more and 0.95 mm or less. Weft threads a and b may have different diameters. In that case, the difference in diameter between weft threads a and b may be, for example, 0.1 mm or more and 0.8 mm or less, particularly 0.2 mm or more and 0.7 mm or less, and more particularly 0.3 mm or more and 0.6 mm or less. The larger the difference in diameter between weft threads a and b, the clearer the pattern in the third and fourth regions of the formed nonwoven fabric tends to be. However, if the difference is too large, the woven structure B and the fiber web may not come into contact (the gap may be large) near the boundary between woven structure A and woven structure B, and conversely, a clear pattern may not be formed. Furthermore, the warp threads that make up the support are common to both weave structures A and B, and their thickness is the same in both weave structures A and B.

[0055] The diameters of the warp and weft threads are determined by the length of the longest line segment connecting any two points in the cross-section (the cross-section obtained by cutting perpendicular to the length direction) of the thread (e.g., filament). This method can also be used to determine the diameter of threads with elliptical, polygonal, or star-shaped cross-sections. However, as described later, for filaments with a flattened cross-section (including rectangles with rounded corners), the dimensions of the short and long sides of the rectangle circumscribing the cross-section are used to indicate its thickness.

[0056] The warp and weft threads constituting the pattern-forming support may be monofilaments having a flattened cross-section, with a rectangle circumscribing the cross-section having a short side of 0.2 mm to 0.8 mm and a long side of 0.3 mm to 1.2 mm. The short side of the circumscribing rectangle may be particularly 0.4 mm to 0.6 mm, and the long side may be particularly 0.7 mm to 0.9 mm. Here, "flattened shape" refers to shapes with large dimensions in one direction, such as rectangles, ellipses, and rectangles with rounded corners, where it is difficult to conceptualize the dimensions and shape solely by the diameter obtained by the above method. If the cross-section is a perfect rectangle, the short and long sides of the rectangle will have dimensions within the above range. The ratio of the length of the long side to the length of the short side of the circumscribing rectangle (long side / short side ratio) may be, for example, 1.2 or more, particularly 1.3 to 3, and more particularly 1.4 to 2.

[0057] In this embodiment, it is preferable that the warp threads constituting the pattern-forming support are flattened. When flattened warp threads are used, the contact area between the warp threads and the fiber web is larger compared to when warp threads with a circular cross-section are used, and the area of ​​openings and / or recesses formed by the floating portions of the warp threads, including knuckles, tends to be larger.

[0058] The warp and weft threads constituting the pattern-forming support may be made of one or more materials selected from polyester, polyamide, polyolefin, polyetheretherketone, and polyphenylene sulfide. Furthermore, the warp and weft threads may be in forms other than monofilament, such as multifilament or spun yarn. In the case of multifilament, fineness may be used instead of diameter as an indicator of yarn thickness, and weft threads a and b with different fineness may be used.

[0059] The weaving density of the pattern-forming support may be, for example, 6 threads / inch to 123 threads / inch for the warp threads, particularly 10 threads / inch to 80 threads / inch, and more particularly 20 threads / inch to 40 threads / inch. The weaving density of the weft threads may be, for example, 6 threads / inch to 123 threads / inch, particularly 8 threads / inch to 60 threads / inch, and more particularly 10 threads / inch to 20 threads / inch. The higher the weaving density, the easier it is to impart a clearer pattern to the nonwoven fabric due to the floating areas of warp threads containing knuckles. However, if the weaving density is too high, the smoothness of the floating areas of warp threads containing knuckles increases, which can actually reduce the clarity of the pattern.

[0060] When the weave structure A is a twill weave, the shape of the diagonal pattern in the first region changes not only with the diameter of the monofilaments, the warp density, and the weft density, but also with the number of warp threads floating above and / or below the weft in the twill weave. The twill weave structure consists of warp threads floating above adjacent or non-adjacent locations. When the floating warp threads are connected by a straight line, if a straight line extending diagonally can be drawn that includes all the floating locations, a first region with a diagonal pattern as shown in Figures 3 and 6 is obtained. If such a straight line cannot be drawn, a first region with a pattern of less regularity in the arrangement of openings or recesses, as shown in Figure 4, is obtained.

[0061] When the weave structure B is a plain weave, the dimensions of the openings formed in the second region change depending on the diameter of the monofilaments that make up the structure, and the larger the diameter of the monofilaments, the larger the area of ​​the openings or depressions tends to be. In addition, the spacing between openings, between openings and depressions, or between depressions changes depending on the weft density and warp density of the plain weave, and the spacing tends to become narrower as the weft density and / or warp density increase.

[0062] In a pattern-forming support, weave structures A and B may both be plain weaves. In this case, the two weave structures can be made different from each other by changing the diameter of the weft threads and / or the density of the weft threads. Alternatively, weave structures A and B may both be twill weaves. In this case, the two weave structures can be made different from each other by using one method selected from changing the number of warp threads floating above the weft threads, changing the number of warp threads submerged beneath the weft threads, changing the diameter of the weft threads, etc.

[0063] If the weave structure B is a fine plain weave (for example, 80 mesh to 100 mesh), a patternless second region is formed corresponding to that structure. In this case, the weave structure A may be a structure capable of forming a pattern, such as a twill weave, or a plain weave consisting of large diameter filaments.

[0064] After performing a pattern-forming entanglement treatment, the fiber web is subjected to a drying treatment to obtain the nonwoven fabric of Embodiment 2, which will be described later. The nonwoven fabric of Embodiment 2 corresponds to the one already described with reference to Figures 3, 4, and 6, and its configuration details will be described later.

[0065] If the fiber web contains adhesive fibers, an bonding treatment may be performed simultaneously with or after the drying treatment to obtain a nonwoven fabric in which the fibers are bonded to each other. The bonding treatment may be a heat bonding treatment, electron beam irradiation bonding, or ultrasonic welding. With heat treatment, the adhesive fibers (e.g., low-melting-point components of composite fibers) can melt or soften upon heating during the heat treatment, thereby bonding the fibers constituting the fiber web to each other. With heat treatment, the drying treatment can be performed simultaneously.

[0066] Heat treatment may include, for example, hot air processing, hot roll processing (hot embossing roll processing), or heat treatment using infrared radiation. Hot air processing may be carried out using a device that blows hot air at a predetermined temperature onto the fiber web, such as a hot air penetration heat treatment machine or a hot air blowing heat treatment machine.

[0067] The heat treatment temperature (for example, the temperature of the hot air) may be the temperature at which the component constituting the adhesive fiber, which functions as an adhesive component, softens or melts. For example, the heat treatment temperature may be a temperature above the melting point of the component. For example, if the adhesive fiber contains polyethylene as a component and polyethylene is used as the adhesive component, the heat treatment temperature may be 130°C to 150°C.

[0068] (Embodiment 2: Nonwoven fabric) The nonwoven fabric described as Embodiment 2 is a nonwoven fabric in which the first entangled portion and the second entangled portion are arranged in a striped pattern, The second confluence includes at least a first region and a second region, In a plan view, when the direction in which the first and second entangled portions extend continuously is defined as the X direction, and the direction perpendicular to the X direction is defined as the Y direction, the first region and the second region are repeatedly and alternately arranged in the X direction. The first entangled portion, the first region, and the second region have different patterns from each other. It is a nonwoven fabric.

[0069] [First confounding section, second confounding section] The nonwoven fabric of this embodiment has a first entanglement portion and a second entanglement portion, and these entanglement portions are arranged in a striped pattern. The first and second entangled portions are both areas where fibers are intertwined and extend along one direction of the nonwoven fabric. In this embodiment, the direction in which the first and second entangled portions extend is defined as the X direction, and the direction perpendicular to the X direction is defined as the Y direction. The X direction may be the longitudinal direction (also called the "MD direction") or transverse direction (also called the "CD direction") of the nonwoven fabric, or it may be a direction that forms an angle with the MD direction or the CD direction.

[0070] As described later, the first and second entanglements may be meandering. In that case, if the two types of entanglements meander between two straight lines parallel to the MD direction of the nonwoven fabric, the first and second entanglements shall be considered to extend along the MD direction of the nonwoven fabric, and the X direction shall be the MD direction. Similarly, if the first entanglement meanders between two straight lines parallel to the CD direction of the nonwoven fabric, the first entanglement shall be considered to extend along the CD transverse direction of the nonwoven fabric, and the X direction shall be the CD direction.

[0071] The first and second entangled areas are distinguished by the fact that the patterns they each possess are different. Here, "pattern" includes "no pattern." "No pattern" refers to something that does not convey a sense of design, and may have, for example, unevenness in the surface texture that occurs unavoidably during web formation, or nozzle lines that occur unavoidably during water flow entanglement processing, but without any intentional pattern being added. More specifically, if the longest dimension of a protrusion, recess, or opening (excluding the dimension in a direction that extends continuously in one direction, such as a nozzle line) is 0.1 mm or less, then such protrusion, recess, or opening is not considered to form a pattern.

[0072] The first entangled portion may be patternless. As described in Embodiment 1, when the nonwoven fabric of this embodiment is manufactured by performing a pattern-forming entanglement process after an overall entanglement process, the first entangled portion has a pattern determined by the support used during the overall entanglement process. If a support with a large mesh count is used in the overall entanglement process, the first entangled portion is formed as patternless.

[0073] The second entanglement portion has first and second regions formed alternately along the X direction, and may further have a narrow third region at the boundary between the first and second regions, or it may have narrow third and fourth regions at the boundary between the first and second regions. The first to fourth regions will be described later. In this embodiment, the nonwoven fabric exhibits a unique design effect that is not a simple striped pattern, due to the second entanglement portion having two or more regions, with the first entanglement portion having a uniform pattern in one direction and the second entanglement portion exhibiting a horizontal striped or ladder-like appearance.

[0074] The Y-direction dimension of each first entanglement (hereinafter referred to as "width" for convenience) may be, for example, 2 mm to 200 mm, particularly 3.5 mm to 100 mm, more particularly 4 mm to 50 mm, even more particularly 5 mm to 30 mm, or 5 mm to 15 mm. In a single first entanglement, the width may be constant or not.

[0075] In nonwoven fabrics, first entanglements of different widths may exist. For example, narrow (e.g., 2mm to 5mm) first entanglements and wide (e.g., 6mm to 15mm) first entanglements may be arranged alternately. Alternatively, narrow (e.g., 2mm to 3mm) first entanglements, medium (e.g., 4mm to 5mm) first entanglements and wide (e.g., 6mm to 15mm) first entanglements may be arranged in the order of narrow / medium / wide or narrow / wide / medium.

[0076] The width of each second confluence may be 2 mm to 200 mm, particularly 3.5 mm to 100 mm, more particularly 4 mm to 50 mm, even more particularly 5 mm to 30 mm, or 5 mm to 15 mm. In a single second confluence, the width may be constant or not.

[0077] In nonwoven fabrics, second entanglements of different widths may exist. For example, narrow (e.g., 2mm to 5mm) second entanglements and wide (e.g., 6mm to 15mm) second entanglements may be arranged alternately. Alternatively, narrow (e.g., 2mm to 3mm) second entanglements, medium (e.g., 4mm to 5mm) second entanglements, and wide (e.g., 6mm to 15mm) second entanglements may be arranged in the order of narrow / medium / wide or narrow / wide / medium.

[0078] In a nonwoven fabric, the first entanglement portion may be linear or meandering. If the first confluence is meandering, the length of the meander per period (i.e., wavelength) may be 5 mm or more. The length of the meander per period is determined as follows: i) As shown in Figure 10, the direction parallel to the line perpendicular to the X direction 31 on which the first entangled portion 42 extends (i.e., the Y direction) is defined as the orthogonal direction, the direction extending towards the "+" side is defined as the positive orthogonal direction 32a, and the direction extending towards the "-" side is defined as the negative orthogonal direction 32b. ii) At point e, where the meandering of the first confluence 42, which was moving toward the negative orthogonal direction 32b (since the first confluence 42 has width, we focus on the movement of one end in the width direction (the left end in the figure)), changes toward the positive orthogonal direction 32a, a straight line 33 perpendicular to the length direction 31 is drawn. iii) At point f, where the meandering of the first entangled portion 42, which was proceeding from point e toward the positive orthogonal direction 32a, progresses toward the negative orthogonal direction 32b and then changes again toward the positive orthogonal direction 32a, a straight line 34 perpendicular to the length direction 31 is drawn. iv) The distance l between line 33 and line 34 is defined as the length of the meander per period. At the point where the meandering of the first entanglement 42 changes from a negative orthogonal direction 32b to a positive orthogonal direction 32a, if the first entanglement 42 moves in a straight line in the longitudinal direction 31 (for example, in the case of a meandering like a rectangular wave), then straight lines 33 and 34 perpendicular to the longitudinal direction 31 are drawn at the midpoint of the straight portion. In Figure 3, reference numeral 41 indicates a second entanglement formed between the first entanglement 42s.

[0079] In this embodiment, the upper limit of the wavelength may be 200 mm. The wavelength is particularly between 10 mm and 150 mm, and more particularly between 30 mm and 100 mm. This allows the meandering pattern to be clearly visible in the nonwoven fabric.

[0080] The meandering of the first confluence is preferably such that it has an amplitude of 1 mm or more. The amplitude is determined as follows. i) As shown in Figure 10, let g be a point that lies on the straight line 33 described above and divides the width of the first entanglement portion 42 into equal parts. ii) At point i, where the meandering of the first entangled portion 42, which was progressing in the positive orthogonal direction 32a, changes to the negative orthogonal direction 32b, a straight line 35 is drawn perpendicular to the length direction 31, and point h is located on this straight line 35 and divides the width of the first entangled portion 42 into equal parts. iii) The amplitude is defined as the distance j between a straight line 36 that includes point g and is parallel to the length direction 31, and a straight line 37 that includes point i and is parallel to the length direction. The upper limit of the amplitude may be 200 mm. The amplitude is particularly between 2 mm and 150 mm, more particularly between 5 mm and 100 mm, and even more particularly between 10 mm and 50 mm.

[0081] The meandering of the first entanglement may have different lengths per period, different amplitudes like a damped wave, and these meanders may be repeated regularly. A preferred configuration of the meandering is one in which the length of the meandering per period is the same and the amplitude is the same, i.e., a repetition of the same pattern. Such a meandering first entanglement gives an orderly impression. Furthermore, such a meandering first entanglement does not give the impression that the design differs greatly between products when the nonwoven fabric is cut as appropriate.

[0082] The ratio of the length (wavelength) to the amplitude per period of the meander (wavelength / amplitude) may be, for example, 1 to 15, particularly 1.5 to 12, and more particularly 2 to 8. If the value of the wavelength-to-amplitude ratio is less than 1 or greater than 15, it may be difficult to recognize that the first confluence is meandering. Figure 3 shows an example where the phases of the meanders of adjacent first confluences are the same. The phases of the meanders of adjacent first confluences may be shifted.

[0083] If the nonwoven fabric has only a first and a second confluence, and the first confluence is meandering, then the second confluence adjacent to the first confluence will also meander. In this case, the length and amplitude of the meandering per period of the second confluence are determined by those of the first confluence. Therefore, a description of the length and amplitude of the meandering per period of the second confluence is omitted here.

[0084] [The first to third regions, and the fourth region] Next, we will describe the first and second regions formed in the second confluence, as well as the third and fourth regions which may be formed. These regions exist in a striped pattern and have distinct patterns from each other. The meaning of "pattern" here is as explained earlier regarding the first and second confluence regions. In this embodiment, these regions are arranged regularly in the X direction. For example, if the second entanglement has a first region and a second region, the first and second regions may be arranged alternately in a repeating pattern. If the second entanglement further has a third region, the first, third, and second regions may be formed in that order. Note that the repeating pattern of first → third → second along one direction becomes the repeating pattern of first → second → third in the opposite direction.

[0085] The patterns of the first and second regions are not particularly limited in form, as long as these regions have different patterns from each other. For example, the first region may be patternless and the second region may have a pattern.

[0086] The pattern may be formed, for example, by the regular arrangement of areas with lower fiber density ("low-density areas") and areas with higher fiber density ("high-density areas"). In this case, the low-density areas may be at least one pattern selected from the group consisting of regular patterns, such as dot patterns, herringbone patterns, checkerboard patterns, grid patterns, houndstooth patterns, diagonal (twill) patterns, satin weave patterns, wave patterns, and zigzag patterns.

[0087] Low-density regions may be less thick than high-density regions and may be recesses that are lower than the high-density regions, or they may be openings where fibers are absent. In a single region, recesses and openings may be mixed as low-density regions. In particular, when forming openings, depending on the manufacturing conditions, it may not be possible to make all low-density regions into openings, and some low-density regions may remain as recesses. Such forms are also acceptable in this embodiment.

[0088] In this embodiment, the pattern of the first region is preferably a diagonal line pattern. The diagonal line pattern is a pattern in which low-density regions and high-density regions extending in a diagonal direction are arranged alternately, and in this embodiment, "diagonal direction" refers to a direction that is not parallel to the MD direction and CD direction of the nonwoven fabric. Regions having a diagonal line pattern tend to improve wiping performance when the nonwoven fabric is used as a wiper, for example.

[0089] If the first region has a diagonal pattern, the acute angle a (see Figure 7) formed by the diagonal lines of the pattern and the direction in which the first region extends may be between 10 degrees and 80 degrees, more particularly between 15 degrees and 75 degrees, and more particularly between 20 degrees and 70 degrees. If the acute angle a is too small, the direction of the diagonal lines approaches the direction in which the first region extends (Y direction), and if the acute angle a is too large, the direction of the diagonal lines approaches the direction perpendicular to the direction in which the first region extends (X direction), making it difficult to recognize the pattern as a diagonal line. Furthermore, in either the case where the acute angle a is too small or too large, it becomes difficult to obtain the effect of improving wiping performance, etc., when using nonwoven fabric as a wiper.

[0090] When the first region has a diagonal pattern, diagonal lines S1, in which openings or recesses are arranged in a straight line, and diagonal lines S2, in which no openings or recesses are formed, or if they are formed, the openings or recesses are smaller than those of diagonal line S1, may be arranged alternately. Diagonal lines S1 are formed by using a support having a twill weave section as the weave structure A, where the number of warp thread floats is 2 or more, as described with reference to Figure 5. When openings or recesses are formed in diagonal lines S1, the area M1 of one opening or recess is, for example, 0.3 mm². 2 More than 3mm 2 The following may be used, especially 0.5 mm 2 2.7mm 2 Below, in particular, 0.7mm 2 2.5mm or more 2 The following may apply: The average diameter of a single opening or recess may be, for example, 1 mm or more and 5 mm or less, more particularly 1.2 mm or more and 4 mm or less, and more particularly 1.5 mm or more and 3 mm or less. Here, the average diameter of an opening or recess refers to the longest length of the line segment connecting any two points that form the contour of the opening, and the average diameter is expressed as the average of the diameters of five or more openings or recesses formed in a single area. If the opening or recess is elliptical, the major axis becomes the diameter of the opening.

[0091] If the area or average diameter of the opening or recess formed in the first region is too large, the strength of the nonwoven fabric may decrease. Also, if an opening is formed, if the area or average diameter of the opening is too large, for example, when the nonwoven fabric is used as a wiper, the wiped dirt may adhere to the hands or jigs through the opening, or the wiped dirt may easily detach from the opening. If the area or average diameter of the opening or recess formed in the first region is too small, it may not be possible to recognize that an opening or recess has been formed, and the design effect may not be obtained.

[0092] Also, in the slanted line S1, the distance between openings, between recesses, or between an opening and a recess may be, for example, 0.5 mm or more and 4.5 mm or less, particularly 0.7 mm or more and 4.0 mm or less, and more particularly 1.0 mm or more and 3.5 mm or less. Here, the distance between openings, between recesses, or between an opening and a recess refers to the shortest of the line segments connecting the centers of all combinations of adjacent openings and recesses. In the case of an opening or a recess formed on the slanted line, the distance between the openings is the distance indicated by the symbol Da in FIG. 8.

[0093] The second region may be a pattern in which openings or recesses are regularly arranged. The pattern in which openings or recesses are regularly arranged may be, for example, a pattern in which openings or recesses are arranged in a staggered pattern, a pattern in which openings or recesses are arranged in a square array, or the like. In the pattern in which openings or recesses are regularly arranged, the distance between openings, between recesses, or between an opening and a recess may be, for example, 1.0 mm or more and 4.0 mm or less, particularly 1.3 mm or more and 3.0 mm or less, and more particularly 1.6 mm or more and 2.5 mm or less. Here, the meaning of the distance between openings, between recesses, or between an opening and a recess is as described in relation to the slanted line S1 that can be formed in the first region. Therefore, for example, as shown in FIG. 9, when openings or recesses are formed in a staggered pattern, the shortest distance between the centers of adjacent openings or recesses is the distance indicated by the symbol Db.

[0094] When the second region is a pattern formed by a regular arrangement of openings or recesses, the area M2 of one opening or recess may be, for example, 1.0 mm 2 or less, particularly 0.8 mm 2 or less, and more particularly 0.6 mm 2 or less. The lower limit of the area of the opening or recess may be, for example, 0.01 mm 2 or more, particularly 0.02 mm 2 or more, and more particularly 0.03 mm 2It may be the case that the average diameter of the opening or recess is, for example, 0.5 mm or more and 4.0 mm or less, particularly 0.6 mm or more and 3.5 mm or less, and more particularly 0.7 mm or more and 3 mm or less. If the area of ​​the opening or recess is too large or the average diameter is too large, the strength of the nonwoven fabric may decrease. Also, if an opening is formed, if the area of ​​the opening or the average diameter is too large, when the nonwoven fabric is used as a wiper, the wiped dirt may adhere to the hands or jigs through the opening, or the wiped dirt may easily detach from the opening.

[0095] If the second region is a pattern formed by the regular arrangement of openings, the proportion of the second region occupied by the openings may be, for example, 1% to 30%, particularly 3% to 20%, and more particularly 5% to 10%. If the proportion of the second region occupied by the openings is too small, the improvements in design and wipeability due to the formation of the openings may not be obtained. If the proportion of the region occupied by the openings is too large, the strength of the nonwoven fabric may decrease, and when used as a wiper, the wiped dirt may adhere to the hands or jigs through the openings, or the wiped dirt may easily detach from the openings.

[0096] If either the first or second region is unpatterned, the other region may have a diagonal pattern or a pattern formed by the regular arrangement of openings. In particular, when the other region has a diagonal pattern, the difference in thickness between it and the unpatterned region becomes larger, which tends to improve the scraping performance when used as a wiper.

[0097] In the nonwoven fabric of this embodiment, the second entanglement portion may further have a third region. In a plan view, when the direction in which each region extends continuously is defined as the Y direction and the direction perpendicular to the Y direction is defined as the X direction, the third region may have a dimension of 9 mm or less in the X direction, particularly 7 mm or less, and more particularly 5 mm or less. The dimension of the third region in the X direction is approximately equivalent to the dimension of the opening or recess formed in the third region in the X direction. As described in Embodiment 1, since the third region is formed in correspondence with the boundary between the woven structures of the support, in which two different woven structures are repeatedly formed, it is formed as a narrow region, and in particular, it may be formed as a linear region whose dimension in the X direction is approximately the size of one opening or recess.

[0098] In the third region, at least one or both of a plurality of openings and recesses arranged linearly in the Y direction are formed. In the third region, openings and recesses may be mixed; for example, a plurality of openings arranged continuously in a linear fashion may be mixed with a plurality of recesses arranged continuously in a linear fashion. Alternatively, when openings and recesses are mixed, they may be arranged linearly without any regularity. Recesses may be, for example, parts where the rearrangement was insufficient during the rearrangement of fibers by water flow entanglement treatment and did not result in the formation of openings. Alternatively, in the third region, no openings may be formed, and only recesses may be formed, and these recesses may be formed not only from knuckles but also from parts where the weft threads are floating, and these recesses may be arranged regularly to form a pattern. In nonwoven fabrics using fiber webs that are less susceptible to rearrangement by water flow, such as nonwoven fabrics with a higher basis weight and laminated nonwoven fabrics, only recesses are likely to be formed in the third region.

[0099] The third region exhibits a different pattern from the first and second regions because at least one of the shapes, dimensions, and spacing of the openings and / or recesses in the third region differs from those in the other regions. This, combined with its smaller dimension in the X direction, gives the third region a stitch-like or cut-line-like appearance, making the boundary between the first and second regions more distinct. If either the first or second region is unpatterned, the third region will naturally have a different pattern from the unpatterned region in that it has either or both openings and recesses.

[0100] The area M3 of the opening or recess formed in the third region (the area of ​​one opening or recess) is, for example, 0.3 mm. 2 4.0mm or more 2 The following may be used, especially 0.4 mm 2 3.5mm or more 2 Below, in particular, 0.5mm 2 3.0mm or more 2 The following may apply: The average diameter of a single opening or recess may be, for example, 0.5 mm or more and 4.0 mm or less, particularly 0.7 mm or more and 3.5 mm or less, and more particularly 1 mm or more and 3 mm or less. In order to increase the average diameter or area of ​​the openings or recesses in the third region, it is necessary to increase the diameter of the warp threads of the striped pattern-forming support used during manufacturing, but weaving with large-diameter warp threads tends to be difficult, and it is difficult to increase the average diameter of the openings or recesses indefinitely. If the average diameter of the openings or recesses in the third region is too small, the pattern in the third region may be difficult to recognize as different from the patterns in the first and second regions.

[0101] When the basis weight of the non-woven fabric is large or the like, in the third region, only concave portions may be formed. In such a case, depending on the type of the pattern formation support used in the production of the non-woven fabric, two types of concave portions may be formed. In this case, the above-mentioned average diameter or area shall be those of the concave portions formed corresponding to the knuckles (portions where the warp threads float) of the support. The concave portions formed corresponding to the knuckles (portions where the warp threads float) of the support are often formed in the non-woven fabric as vertically long ones having a deeper depth of the concave portion and a longer dimension in the X direction.

[0102] When the average diameter of the openings or concave portions formed in the first region is L1, the average diameter of the openings or concave portions formed in the second region is L2, and the average diameter of the openings or concave portions formed in the third region is L3, L3 may be larger than either L1 or L2. By L3 being the largest, the third region can be more emphasized at the boundary between the first region and the second region, and the design effect of the non-woven fabric can be enhanced more.

[0103] The relationship among the areas M1, M2, and M3 per one of the openings or concave portions formed in each region is affected by the weave structure of the striped pattern formation support used in the production of the non-woven fabric. For example, in a non-woven fabric produced using a support as shown in FIG. 1, the relationship of M1≦M2<M3 may be satisfied, and further, the relationship of M3 / M2≧1.2, more particularly M3 / M2≧1.5, and even more particularly M3 / M2≧2.0 may be satisfied. This is because, like the support shown in FIG. 1, the number of floating warp threads is smaller compared to the number of floating weft threads in the weave structure A, and it is more difficult to form openings or concave portions in the first region. When M3 and M2 satisfy or do not satisfy the above relationship, when openings and / or concave portions are formed in the first region, M3 and M1 may satisfy the relationship of M3 / M1≧1.2, more particularly M3 / M1≧1.3.

[0104] Note that there may be no openings or recesses formed in the first region and / or the second region, and M1 and / or M2 may be substantially zero. In this case, M3 / M2 cannot be determined. However, even when M1 and / or M2 are zero, since the third region and the first region are more clearly distinguishable, it is assumed that the relationship M3 / M2 ≥ 1.2 is satisfied.

[0105] Also, for example, in a nonwoven fabric produced using the support shown in FIG. 2, the relationship M2 < M1 < M3 may be satisfied, and furthermore, the relationship M3 / M1 ≥ 1.2, more particularly M3 / M1 ≥ 1.3 may be satisfied. In the support shown in FIG. 2, since the number of floats of the weft yarns of the woven structure A is smaller compared to the support of FIG. 1, openings are relatively likely to be formed in the first region. Therefore, in order to distinguish the third region from the first region, it is possible to define the relationship between M3 and M1, and by satisfying M3 / M1 ≥ 1.2, the third region is more emphasized.

[0106] The distance between openings, between recesses, or between an opening and a recess formed in the third region may be, for example, 1 mm or more and 9 mm or less, particularly 2 mm or more and 8 mm or less, and more particularly 2.5 mm or more and 7 mm or less. Here, the distance between openings, between recesses, or between an opening and a recess is, as described in relation to the oblique line S1 that can be formed in the first region, the shortest among the line segments connecting the centers in all combinations of adjacent openings, an adjacent opening and a recess, and adjacent recesses. In the third region, when openings and recesses are mixed, it is preferable that the distances between openings, between recesses, and between an opening and a recess all satisfy the above range. Since the openings and / or recesses in the third region are linearly arranged in a row in the Y direction, the distance between openings, between recesses, or between an opening and a recess is generally the distance in the Y direction.

[0107] In the nonwoven fabric of this embodiment, the second entanglement portion may further have a fourth region. The fourth region is formed at the boundary between a first region (or second region) and the second region (or first region) on the opposite side from where the third region is formed, when viewed from one first region (or second region). That is, the fourth region, like the third region, is formed corresponding to the boundary between the woven structures of the support, in which two different woven structures are repeatedly formed. In a nonwoven fabric having a fourth region, the four regions are formed in the order of first region, third region, second region, and fourth region in the X direction. Note that the repetition of 1st → 3rd → 2nd → 4th along one direction becomes 1st → 4th → 2nd → 3rd in the opposite direction.

[0108] The fourth region, in plan view, has dimensions of 9 mm or less in the X direction, particularly 8 mm or less, more particularly 6 mm or less, and even more particularly 4 mm or less. The X-direction dimension of the fourth region is approximately equivalent to the X-direction dimension of the opening or recess formed in the fourth region. Similar to the third region, the fourth region is formed in correspondence with the boundary between the weave structures of the support, where two different weave structures are repeatedly formed. Therefore, it is formed as a narrow region, and in particular, it may be formed as a linear region whose X-direction dimension is approximately the size of one opening or recess. The dimensions of the fourth region are determined by the weave structure of the pattern-forming support and the thickness of wefts a and b, etc. For example, when using a support as shown in Figure 5, the fourth region is formed by knuckles N2 and N3 with a warp float count of 2, so its X-direction dimension is smaller than that of the third region, which is formed by knuckle N1 with a warp float count of 3.

[0109] In the fourth region, at least one or both of a plurality of openings and recesses arranged linearly in the Y direction are formed. In the fourth region, openings and recesses may be mixed; for example, a plurality of continuously arranged linear openings may be mixed with a plurality of continuously arranged linear recesses. Alternatively, when openings and recesses are mixed, they may be arranged linearly without any regularity. Recesses may be, for example, parts where the rearrangement was insufficient during the rearrangement of fibers by water flow entanglement treatment and did not result in the formation of openings. Alternatively, in the fourth region, no openings may be formed, and only recesses may be formed, and these recesses may be formed not only from knuckles but also from parts where the weft threads are floating, and these recesses may be arranged regularly to form a pattern. In nonwoven fabrics using fiber webs that are less susceptible to rearrangement by water flow, such as nonwoven fabrics with a higher basis weight and laminated nonwoven fabrics, only recesses are likely to be formed in the fourth region.

[0110] The fourth region exhibits a different pattern from the first and second regions by having at least one of the shapes, dimensions, and spacing of the openings and / or recesses of the fourth region that differ from those of the first and second regions. Thus, the fourth region, like the third region, has the appearance of seams (stitch-like) or cut lines, coupled with its smaller dimension in the X direction, making the boundary between the first and second regions more distinct. If either the first or second region is unpatterned, the fourth region will naturally have a different pattern from the unpatterned region in that it has openings and / or recesses, or both. The fourth region may have the same pattern as the third region, or it may have a different pattern.

[0111] The area of ​​the opening or recess formed in the fourth region (the area of ​​one opening or recess) is, for example, 0.5 mm. 2 3.5mm or more 2 The following may be used, especially 0.7 mm 2 More than 3mm 2 Below, in particular, 1mm 2 2.5mm or more 2The following may be applicable. The average diameter of one opening or recess may be, for example, 0.5 mm or more and 5 mm or less, particularly 1 mm or more and 4 mm or less, and more particularly 2 mm or more and 3 mm or less. The reason for exemplifying the above as the range of the average diameter or area of the openings or recesses in the fourth region is as described above in relation to the average diameter and area of the openings or recesses in the third region.

[0112] In cases where the basis weight of the non-woven fabric is large, etc., only recesses may be formed in the fourth region. In such cases, depending on the type of the pattern formation support used in the production of the non-woven fabric, etc., two types of recesses may be formed. In this case, the above-mentioned average diameter or area shall be that of the recesses formed corresponding to the knuckles (parts where the warp threads float) of the support. The recesses formed corresponding to the knuckles (parts where the warp threads float) of the support are often formed in the non-woven fabric as vertically long ones having a deeper depth and a longer dimension in the X direction.

[0113] As described above, when the diameters of the openings or recesses formed in the first region to the third region are L1 to L3 respectively, and the diameter of the openings or recesses formed in the fourth region is L4, L4 may be larger than either L1 or L2. The relationship between L3 and L4 is not particularly limited, and L3 = L4 may be applicable, or L3 > L4, or L3 < L4 may be applicable. Since L4 is larger than either L1 or L2, the fourth region is more emphasized at the boundary between the first region and the second region, and the design effect of the non-woven fabric can be enhanced more.

[0114] The relationship among M1, M2, M3, and M4 is affected by the weave structure of the pattern-forming support used in nonwoven fabric production. For example, in the nonwoven fabric produced using the support shown in FIG. 5, the relationships of M2 < M1 < M3 and M2 < M1 < M4 may be satisfied. Further, the relationships of M3 / M2 ≥ 1.2, particularly M3 / M2 ≥ 1.3, and / or M4 / M2 ≥ 1.2, particularly M4 / M2 ≥ 1.3 may be satisfied. Further, M4 and M1 may satisfy a relationship such as M4 / M1 ≥ 1.2, particularly M4 / M1 ≥ 1.5, more particularly M4 / M1 ≥ 2, and even more particularly M4 / M1 ≥ 3. Further, M3 and M1 may satisfy a relationship such as M3 / M1 ≥ 1.2, particularly M3 / M1 ≥ 1.3, and more particularly M3 / M1 ≥ 1.5.

[0115] The distance between the openings, between the recesses, or between the opening and the recess formed in the fourth region may be, for example, 1 mm or more and 8 mm or less, particularly 2 mm or more and 6 mm or less, and more particularly 3 mm or more and 4 mm or less. Here, the meaning of the distance between the openings, between the recesses, or between the opening and the recess is as described above in relation to the first region.

[0116] As described above, in the nonwoven fabric of the present embodiment, the first region and the second region, and optionally further the third region or the third region and the fourth region, are arranged parallel to each other within the second intersection portion and exist in a pattern repeated in a certain direction to form a pattern. That is, the nonwoven fabric of the present embodiment forms a striped pattern or a ladder-like pattern in the direction (X direction) orthogonal to the direction (Y direction) in which each region extends. The direction in which each region is repeatedly arranged coincides with the direction in which the first intersection portion and the second intersection portion extend. Therefore, the nonwoven fabric of the present embodiment has a striped pattern in which the first intersection portion and the second intersection portion, which are belt-like portions extending in the X direction, are regularly arranged in the Y direction, and the second intersection portion forms another striped pattern or a lattice pattern, presenting a unique appearance that is not a simple striped pattern, but lattice-like or patchwork-like.

[0117] The first region may have dimensions in the X direction of, for example, 2 mm to 200 mm, more particularly 3 mm to 100 mm, more particularly 5 mm to 50 mm, even more particularly 7 mm to 30 mm, and even more particularly 10 mm to 25 mm. The second region may also have dimensions in the X direction of, for example, 2 mm to 200 mm, more particularly 3 mm to 100 mm, more particularly 5 mm to 50 mm, even more particularly 7 mm to 30 mm, and even more particularly 10 mm to 25 mm. The X-direction dimension of the first region (hereinafter referred to as "width" for convenience) and the width of the second region may be the same or different. Furthermore, a single nonwoven fabric may contain multiple first regions of different widths, and / or multiple second regions of different widths.

[0118] If the width of the first area is too small, the design effect resulting from the formation of a striped or grid pattern may not be fully achieved, and if nonwoven fabric is used as a wiper, the wiping performance may be insufficient. The same applies if the width of the second area is too small. If the width of the first area is too large, the design effect may not be fully achieved, and the wiping performance may be insufficient. The same applies if the width of the second area is too large.

[0119] [Fibers that make up nonwoven fabric] The fibers constituting the nonwoven fabric of this embodiment are not particularly limited, and any fibers used in nonwoven fabric manufacturing may be arbitrarily adopted. The nonwoven fabric of this embodiment is, for example, Synthetic fibers made of one or more thermoplastic resins selected from polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate and their copolymers, polyamide resins such as nylon 6, nylon 66 and their copolymers, polyolefin resins such as polymethylpentene, polypropylene, and polyethylene (including high-density polyethylene, low-density polyethylene, and linear low-density polyethylene), acrylic resins, engineering plastics such as polycarbonate, polyacetal, polystyrene, and cyclic polyolefins, and their elastomers. Natural fibers such as cotton, silk, wool, linen, and pulp, as well as Regenerated fibers such as rayon and polynosic obtained by the viscose method, cupro obtained by the copper ammonia method, and cellulosic fibers (such as lyocell and Tencel®) obtained by the solvent spinning method (including those whose surfaces are treated with hydrophobic agents), Cellulose fibers obtained by melt spinning, and Semi-synthetic fibers such as acetate fibers It may be formed of one or more fibers selected from the following.

[0120] The synthetic fiber may be either a single fiber or a composite fiber. The composite fiber may be, for example, a concentric or eccentric core-sheath composite fiber, a sea-island composite fiber, a side-by-side composite fiber, or a split composite fiber.

[0121] Synthetic fibers may also exhibit adhesive properties by melting or softening upon heating or other means. For example, synthetic fibers may be single fibers or composite fibers containing a relatively low-melting-point resin such as polyethylene as one component, with the low-melting-point resin component occupying at least a portion of the fiber surface. Such fibers may be, for example, core-sheath type composite fibers made of a combination of polyethylene / polypropylene or polyethylene / polyethylene terephthalate, where polyethylene is the sheath component, or split-type composite fibers made of a combination of these thermoplastic resins.

[0122] In the case of core-sheath type composite fibers, the composite ratio of core component to sheath component (core component: sheath component) is preferably 80:20 to 20:80 by volume, more preferably 70:30 to 30:70, and even more preferably 60:40 to 40:60.

[0123] In the case of segmented composite fibers, the ratio of the two components (1st:2nd) is preferably 80:20 to 20:80 in volume ratio, more preferably 70:30 to 30:70, and even more preferably 60:40 to 40:60. In the case of segmented composite fibers, the number of segments (i.e., the number of sections in the composite fiber) may be, for example, 4 or more and 32 or less, particularly 4 or more and 20 or less, and more particularly 6 or more and 10 or less.

[0124] When using synthetic fibers that can bond to each other, the amount of such synthetic fibers may be, for example, 5% or more by mass, particularly 10% or more by mass, and more particularly 15% or more by mass, when the total mass of the nonwoven fabric is considered as 100% by mass. The upper limit for the proportion of adhesive synthetic fibers is, for example, 35% by mass, particularly 30% by mass, and more particularly 25% by mass. If the proportion of adhesive synthetic fibers is too low, the effects of bonding the fibers to each other (for example, improvement of the mechanical strength of the nonwoven fabric, suppression of fuzzing, and maintenance of the applied pattern) may not be fully obtained. If the proportion of adhesive synthetic fibers is too high, the texture of the nonwoven fabric becomes hard, reducing its drape, which may affect its wiping performance when used as a wiper.

[0125] The nonwoven fabric of this embodiment may contain, for example, 30% by mass or more, more particularly 50% by mass or more, and more particularly 80% by mass or more, cellulose fibers. Here, examples of cellulose fibers include natural fibers derived from plants such as cotton, linen, ramie, jute, hemp, and pulp; regenerated fibers such as rayon and polynosic obtained by the viscose method, cupro obtained by the copper ammonia method, and cellulose fibers obtained by the solvent spinning method (such as Lenzing Lyocell® and Tencel®); cellulose fibers obtained by the melt spinning method; and semi-synthetic fibers such as acetate fibers. When the nonwoven fabric is manufactured by entanglement treatment using high-pressure fluid flow, the cellulose fibers intertwine easily with each other, and the entangled state is well maintained even after the entanglement treatment, thus making it easy to form a clear pattern on the nonwoven fabric. In addition, the good intertwining of the fibers suppresses fluffing of the nonwoven fabric.

[0126] The fineness of the fibers is not particularly limited and is selected according to the application of the nonwoven fabric. For example, the fineness of the fibers may be between 0.3 dtex and 10 dtex, more particularly between 0.5 dtex and 5.0 dtex, more particularly between 0.7 dtex and 4.0 dtex, even more particularly between 1.0 dtex and 3.0 dtex, and even more particularly between 1.3 dtex and 2.5 dtex. When the fibers constituting the nonwoven fabric are natural fibers such as cotton, it may be difficult to use fibers within a specific fineness range, in which case fibers of various finenesses may be included. If the fineness of the fibers is too low, when the nonwoven fabric is manufactured by entanglement treatment using high-pressure fluid flow, the fibers may become entangled with the support, or clogging may occur in the support. If the fineness of the fibers is too high, the pattern may become unclear.

[0127] The fiber length is not limited and is selected according to the manufacturing conditions of the nonwoven fabric. For example, the fiber length is 10 mm to 100 mm. If the fiber length is outside this range, it may be difficult to produce a fiber web using, for example, a carding machine. Also, in low-basis-weight nonwoven fabrics, if the fiber length exceeds 100 mm, the number of fibers constituting the nonwoven fabric decreases, which may result in an unstable nonwoven fabric structure or failure to obtain the required nonwoven fabric strength. Furthermore, if the fiber length is too short, the strength of the nonwoven fabric may decrease, and if the fiber length is too long, the pattern may not be clear. The fiber length is more preferably 25 mm to 90 mm, even more preferably 32 mm to 70 mm, and particularly preferably 38 mm to 65 mm. Alternatively, if the nonwoven fabric is manufactured by a method that includes producing a fiber web using the air-laying method or the wet papermaking method, the fiber length may be, for example, 2 mm to 20 mm.

[0128] [Form of nonwoven fabric] The nonwoven fabric may have a single-layer structure or a laminated structure. Furthermore, the nonwoven fabric may be formed from a web selected from card webs such as parallel webs, cross webs, semi-random webs, and random webs, as well as air-lay webs, wet-machine webs, melt-blown webs, and spunbond webs. When cellulose fibers constitute all or part of the constituent fibers, a web selected from card webs, air-lay webs, and wet-machine webs may be produced. When these fiber webs containing cellulose fibers are used to produce a nonwoven fabric, particularly by entanglement treatment using high-pressure fluid flow, the fibers intertwine easily, and the entangled state is well maintained even after the entanglement treatment. This facilitates the formation of clear patterns in the nonwoven fabric, and the good intertwining of the fibers suppresses fluffing of the nonwoven fabric.

[0129] Furthermore, the mechanical strength of the nonwoven fabric can be improved by creating a laminated structure that includes an air-lay web, a wet-machine web, a melt-blown web, or a spunbond web.

[0130] [Physical properties of nonwoven fabrics] The physical properties of the nonwoven fabric of this embodiment will be described below as an example. Please note that the physical properties of the nonwoven fabric vary depending on the fibers constituting the nonwoven fabric, the basis weight of the nonwoven fabric, and the manufacturing conditions of the nonwoven fabric, and therefore the nonwoven fabric of this embodiment is not limited to having the following physical properties.

[0131] The thickness of the nonwoven fabric in this embodiment (at a load of 294 Pa) may be, for example, 0.50 mm or more and 1.0 mm or less, particularly 0.55 mm or more and 0.90 mm or less, and more particularly 0.60 mm or more and 0.80 mm or less.

[0132] The basis weight of the nonwoven fabric in this embodiment is not particularly limited and may be appropriately selected depending on the application. For example, when the nonwoven fabric of this embodiment is used as a wiper, its basis weight is 30 g / m². 2 More than 80g / m 2 The following may be used, in particular 35 g / m² 2 ~75g / m 2 It may be 40g / m², and more specifically 40g / m². 2 ~70g / m 2 It may be as follows. Alternatively, when the nonwoven fabric of this embodiment is used as a sanitary product (for example, as a surface material for absorbent articles), its basis weight may be 20 g / m². 2 ~70g / m 2 It is fine if it is 25g / m² 2 ~65g / m 2 It may be 30g / m², and more specifically 30g / m². 2 ~60g / m 2 This may be the case. Depending on the type of fiber used and the structure of the fiber web, the larger the basis weight, the less likely it is that openings will form and the more likely recesses will form in the second entanglement area, or in the case where the third region or the third and fourth regions are formed in these regions. If the basis weight is too large, the pattern may be formed on only one side, and the effect of the pattern may only appear on one side. If the basis weight is too small, a clear pattern may not be formed, and the effect of the pattern may not be achieved.

[0133] (Embodiment 3: Uses of the nonwoven fabric in Embodiment 2) As Embodiment 3, a product using the nonwoven fabric from Embodiment 2 will be described. The nonwoven fabric of Embodiment 2 may be used as a wiper alone or in combination with other nonwoven fabrics or sheet-like materials. When this nonwoven fabric is placed on an object with dirt and rubbed by moving it back and forth in a direction in which the first and second regions are repeatedly formed, it is less likely to wrinkle, and the dirt on the object can be effectively wiped away by the irregularities and openings that form the pattern of the first and second regions of the second entanglement portion.

[0134] Here, wipers include those for use with people and those for use with objects. Wipers for use with people include wipers for wiping dirt off the skin of the human body, as well as wipers for wiping dirt off teeth, and wipers for wiping dirt off the scalp and hair. Wipers for objects may be used for wiping floors, kitchens, toilets, bathtubs, furniture, vehicles, walls, screens, and windows. Wipers for people and objects may be provided in a state in which water or an aqueous solution containing a cleaning component is impregnated in an amount of 100 to 1000 parts by mass per 100 parts by mass of nonwoven fabric.

[0135] Alternatively, the nonwoven fabric of this embodiment may be used in hygiene products such as sanitary napkins, infant diapers, and adult diapers. As described above, the nonwoven fabric of this embodiment has unique water absorption properties, and the absorbed liquid does not easily diffuse in the nonwoven fabric of this embodiment. Therefore, the nonwoven fabric of this embodiment may be used in hygiene products as a component where the spread of blood or excrement needs to be suppressed, especially as a surface material. Alternatively, the nonwoven fabric of this embodiment may be used in wet wipes, face masks, sanitary masks, filters, poultices, etc. [Examples]

[0136] This embodiment will be described below with reference to examples. The following fibers were prepared for use in the examples and comparative examples. Rayon (cellulose fiber): Viscose rayon fiber with a fineness of 1.7 dtex and a fiber length of 40 mm (Corona CD (product name) manufactured by Daiwabo Rayon Co., Ltd.). PP / PE: A concentric core-sheath composite fiber (manufactured by Yamato Spinning Co., Ltd., product name NBF(H)) with a polypropylene core and a high-density polyethylene (melting point: approximately 133°C) sheath, a composite ratio (core:sheath) of 37:63 (volume ratio), a fineness of 1.7 dtex, and a fiber length of 51 mm.

[0137] The pattern-forming supports used in the pattern-forming entanglement treatment for the production of nonwoven fabrics in the examples and comparative examples are shown below. Pattern-forming support 1: A fabric was prepared as support 1 in which weave structure A was a 1 / 7 twill weave section and weave structure B was a plain weave section, with weave structures A and B arranged alternately in the MD direction. In support 1, polyester monofilament with a rounded rectangular cross-section and dimensions of the rectangle circumscribing the cross-section being 0.88 mm long side × 0.57 mm short side was used as the warp threads, and polyester monofilament with a diameter of 0.9 mm was used as the weft thread a and polyester monofilament with a diameter of 0.45 mm was used as the weft thread b. In support 1, the warp density was 30 threads / inch and the weft density was 25 threads / inch, the MD direction dimension of weave structure A was 15 mm and the MD direction dimension of weave structure B was 8 mm. In support 1, the surface of weave structure A was 1.5 mm higher than the surface of weave structure B. Pattern-forming support 2: A fabric was prepared as support 2 in which weave structure A was a 1 / 3 broken twill weave section (broken twill, 4 warp strands per section) and weave structure B was a plain weave section, with weave structures A and B arranged alternately in the MD direction. In support 2, polyester monofilament with a rounded rectangular cross-section and dimensions of the rectangle circumscribing the cross-section being 0.88 mm long side × 0.57 mm short side was used as the warp threads, and polyester monofilament with a diameter of 0.9 mm was used as the weft thread a and polyester monofilament with a diameter of 0.45 mm was used as the weft thread b. In support 1, the warp density was 30 threads / inch and the weft density was 17 threads / inch, the MD direction dimension of weave structure A was 15 mm and the MD direction dimension of weave structure B was 8 mm. In support 2, the surface of weave structure A was 1.0 mm higher than the surface of weave structure B. Pattern-forming support 3: A fabric was prepared as support 3 in which weave structure A was a 2 / 2 twill weave section and weave structure B was a plain weave section, with weave structures A and B arranged alternately in the MD direction. In support 3, polyester monofilament with a rounded rectangular cross-section and dimensions of the rectangle circumscribing the cross-section being 0.88 mm long side × 0.57 mm short side was used as the warp threads, and polyester monofilament with a diameter of 0.9 mm was used as the weft thread a and polyester monofilament with a diameter of 0.45 mm was used as the weft thread b. In support 1, the warp density was 30 threads / inch and the weft density was 17 threads / inch, the MD direction dimension of weave structure A was 20 mm and the MD direction dimension of weave structure B was 10 mm. In support 3, the surface of weave structure A was 0.8 mm higher than the surface of weave structure B.

[0138] Pattern-forming support 4: A fabric was prepared as support 4 in which weave structure A was a 1 / 7 twill weave section and weave structure B was a plain weave section, with weave structures A and B arranged alternately in the MD direction. In support 4, polyester monofilament with a rounded rectangular cross-section and dimensions of the rectangle circumscribing the cross-section being 0.88 mm long side × 0.57 mm short side was used as the warp threads, and polyester monofilament with a diameter of 0.9 mm was used as the weft thread a and polyester monofilament with a diameter of 0.45 mm was used as the weft thread b. In support 4, the warp density was 30 threads / inch and the weft density was 25 threads / inch, the MD direction dimension of weave structure A was 15 mm and the MD direction dimension of weave structure B was 20 mm. In support 4, the surface of weave structure A was 1.6 mm higher than the surface of weave structure B. Pattern-forming support 5: A fabric was prepared as support 5 in which weave structure A was a 2 / 2 twill weave section and weave structure B was a plain weave section, with weave structures A and B arranged alternately in the MD direction. In support 5, polyester monofilament with a rounded rectangular cross-section and dimensions of the rectangle circumscribing the cross-section being 0.88 mm long side × 0.57 mm short side was used as the warp threads, and polyester monofilament with a diameter of 0.9 mm was used as the weft thread a and polyester monofilament with a diameter of 0.45 mm was used as the weft thread b. In support 5, the warp density was 30 threads / inch and the weft density was 17 threads / inch, and the MD direction dimension of weave structure A was 6 mm and the MD direction dimension of weave structure B was 6 mm. In support 5, the surface of weave structure A was 0.6 mm higher than the surface of weave structure B. Pattern-forming support 6: A fabric was prepared as support 6 in which weave structure A was a 2 / 2 twill weave section and weave structure B was a plain weave section, with weave structures A and B arranged alternately in the MD direction. In support 6, polyester monofilament with a rounded rectangular cross-section and dimensions of the rectangle circumscribing the cross-section being 0.88 mm long side × 0.57 mm short side was used as the warp threads, and polyester monofilament with a diameter of 0.9 mm was used as the weft thread a and polyester monofilament with a diameter of 0.45 mm was used as the weft thread b. In support 6, the warp density was 30 threads / inch and the weft density was 17 threads / inch, and the MD direction dimension of weave structure A was 10 mm and the MD direction dimension of weave structure B was 10 mm. In support 6, the surface of weave structure A was 0.45 mm higher than the surface of weave structure B.

[0139] (Example 1) A fiber web was produced by mixing 80% rayon by mass and 20% PP / PE by mass using a parallel carding machine. The basis weight of this fiber web was approximately 40 g / m². 2 That was the case. [Overall confounding treatment] The aforementioned fiber web was placed on a plain weave net with warp thread diameters of 0.132 mm, weft thread diameters of 0.132 mm, and a mesh count of 90. While the fiber web was advanced at a speed of 4 m / min, a columnar water stream at a water pressure of 1.0 MPa was sprayed onto the surface of the fiber web, followed by a columnar water stream at a water pressure of 1.5 MPa on the back surface of the fiber web. A nozzle with orifices of 0.12 mm in diameter spaced 0.6 mm apart was used to spray the water streams. The distance between the surface of the fiber web and the orifices was 15 mm.

[0140] [Pattern formation confounding treatment] The fiber web, after undergoing the overall entanglement treatment, was placed on the pattern-forming support 1, and while the fiber web was advanced at a speed of 4 m / min, a columnar stream of water at a water pressure of 1.5 MPa was sprayed onto the back surface of the fiber web. In the pattern-forming entanglement treatment, a second entanglement section was formed using a nozzle in which some of the multiple orifices were blocked and the orifice group was arranged at predetermined intervals. Specifically, a nozzle was used in which some of the orifices were blocked so that a first entanglement section with a width of 10 mm was formed every 20 mm, with orifices of 0.12 mm in diameter arranged at 0.6 mm intervals. During the water flow entanglement treatment, the nozzle was not vibrated, and the distance between the nozzle and the web was 15 mm. The same nozzle used in the overall entanglement treatment was used for spraying the water flow.

[0141] Through a pattern-forming entanglement process, a nonwoven fabric was obtained having a first entanglement area and a second entanglement area with first to third regions formed, as shown in Figure 3. In the second entanglement area, each region extends along the CD direction (i.e., the CD direction is the Y direction), and the first region consists of a diagonal pattern area, while the second region consists of a pattern area with openings arranged in a staggered pattern, which alternately repeat in the MD direction (X direction), forming a striped pattern. Furthermore, a third region consisting of multiple openings formed along the Y direction was formed between the first and second regions.

[0142] [Heat treatment] The nonwoven fabric after the pattern-forming entanglement treatment was heated at 135°C for approximately 5 seconds using a hot air penetration heat treatment machine to perform a drying treatment, and at the same time, the fibers were heat-bonded together by the PP / PE sheath component to obtain the nonwoven fabric of Example 1. The dimensions of each entanglement and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 1.

[0143] (Example 2) The nonwoven fabric of Example 2 was obtained using the same procedure as that used in the production of Example 1, except that the pattern-forming support 2 was used in the pattern-forming entanglement treatment. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to third regions, as shown in Figure 4. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a patterned area with irregularly formed openings as the first region and a patterned area with staggeredly arranged openings as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Furthermore, a third region consisting of multiple openings formed along the Y direction was formed between the first and second regions. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 1.

[0144] (Example 3) The nonwoven fabric of Example 3 was obtained using the same procedure as that used in the production of Example 1, except that the pattern-forming support 3 was used in the pattern-forming entanglement treatment. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 6. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 1.

[0145] (Example 4) The nonwoven fabric of Example 4 was obtained using the same procedure as that used in the production of Example 1, except that the pattern-forming support 4 was used in the pattern-forming entanglement treatment. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to third regions, as shown in Figure 11. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and the first region consisted of a diagonal pattern area, while the second region consisted of a pattern area with openings arranged in a staggered pattern, which alternately repeated in the MD direction (X direction), forming a striped pattern. Furthermore, a third region consisting of multiple openings formed along the Y direction was formed between the first and second regions. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 1.

[0146] (Example 5) The nonwoven fabric of Example 5 was obtained using the same procedure as in the manufacturing of Example 1, except that the pattern-forming support 5 was used in the pattern-forming entanglement treatment. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 12. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 1.

[0147] (Example 6) The nonwoven fabric of Example 6 was obtained using the same procedure as that used in the production of Example 1, except that the pattern-forming support 6 was used in the pattern-forming entanglement treatment. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 13. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 1.

[0148] (Example 7) The nonwoven fabric of Example 6 was obtained using the same procedure as that used in the production of Example 1, except that in the pattern-forming entanglement process, some of the orifices among the multiple orifices were blocked so that first entangled sections with a width of 6 mm were formed every 6 mm (i.e., second entangled sections with a width of 6 mm and first entangled sections with a width of 6 mm were formed in a striped pattern), a nozzle in which the orifice group was provided at predetermined intervals was used, and a pattern-forming support 6 was used. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 14. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 2.

[0149] (Example 8) The nonwoven fabric of Example 6 was obtained using the same procedure as the one used in the production of Example 1, except that in the pattern-forming entanglement process, some of the orifices among the multiple orifices were blocked so that first entangled sections with a width of 10 mm were formed every 10 mm (i.e., second entangled sections with a width of 10 mm and first entangled sections with a width of 10 mm were formed in a striped pattern), a nozzle in which the orifice group was provided at predetermined intervals was used, and a pattern-forming support 6 was used. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 15. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 2.

[0150] (Example 9) The nonwoven fabric of Example 6 was obtained using the same procedure as the one used in the production of Example 1, except that in the pattern-forming entanglement process, some of the orifices among the multiple orifices were blocked so that first entangled sections with a width of 20 mm were formed every 10 mm (i.e., second entangled sections with a width of 10 mm and first entangled sections with a width of 20 mm were formed in a striped pattern), a nozzle in which the orifice group was provided at predetermined intervals was used, and a pattern-forming support 6 was used. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 16. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 2.

[0151] (Example 10) In the pattern-forming entanglement process, the nonwoven fabric of Example 6 was obtained using the same procedure as the one used in the production of Example 1, except that (i) a nozzle was used in which some of the multiple orifices were blocked so that a first entanglement section with a width of 10 mm was formed every 10 mm (i.e., a second entanglement section with a width of 10 mm and a first entanglement section with a width of 10 mm were formed in a striped pattern), (ii) this nozzle was vibrated along the transverse direction of the web at an amplitude of 80 mm and a vibration speed of 4 m / min, and (iii) a pattern-forming support 6 was used. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 17. The first and second entanglement areas were meandering. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 2.

[0152] (Example 11) The nonwoven fabric of Example 6 was obtained using the same procedure as that used in the production of Example 1, except that in the pattern-forming entanglement process, some of the orifices among the multiple orifices were blocked, and a nozzle in which the orifice group was arranged at predetermined intervals was vibrated along the transverse direction of the web at an amplitude of 80 mm and a vibration speed of 4 m / min, and a pattern-forming support 6 was used. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 18. The first and second entanglement areas were meandering. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 2.

[0153] (Example 12) The nonwoven fabric of Example 6 was obtained using the same procedure as that used in the production of Example 1, except that, in the pattern formation entanglement process, some of the orifices among the multiple orifices were blocked, and a nozzle in which the orifice group was arranged at predetermined intervals was vibrated along the transverse direction of the web at an amplitude of 80 mm and a vibration speed of 4 m / min, and the pattern formation entanglement process and the use of the pattern formation support 2 were performed. A pattern-forming entanglement process yielded a nonwoven fabric having a first entanglement area and a second entanglement area with first to fourth regions, as shown in Figure 18. The first and second entanglement areas were meandering. In the second entanglement area, each region extended along the CD direction (i.e., the CD direction is the Y direction), and a diagonal pattern area as the first region and a pattern area with openings arranged in a staggered pattern as the second region alternately repeated in the MD direction (X direction), forming a striped pattern. Third and fourth regions were formed at the boundary between the first and second regions. In the first region, diagonal lines S1 with openings and diagonal lines S2 without openings were repeatedly and alternately formed. The dimensions of each entanglement area and region of the obtained nonwoven fabric, as well as the configuration of the openings or recesses formed in each region, are shown in Table 2.

[0154] (Comparative Example 1) A nonwoven fabric for Comparative Example 1 was obtained using the same procedure as that used in the production of Example 1, except that a pattern-forming entanglement treatment was not performed. This nonwoven fabric was patternless throughout.

[0155] (Comparative Example 2) In the pattern-forming entanglement process, a fiber web was placed on a support having the following configuration, and while the fiber web was advanced at a speed of 4 m / min, a columnar stream of water at a water pressure of 1.5 MPa was sprayed onto the fiber web using the nozzle used in the overall entanglement process of Example 1 to obtain a nonwoven fabric. The obtained nonwoven fabric had a grid pattern in which patternless entangled sections with a width of approximately 10 mm were arranged vertically and horizontally to form a grid, and the regions between the grids had a herringbone pattern. In the regions between the grids (approximately square regions), only one type of pattern was formed, and no two or more regions with different patterns were formed. The support structure used was a 2 / 1 herringbone weave fabric with 0.66 mm diameter polyester monofilaments as warp threads and 0.89 mm diameter polyester monofilaments as weft threads, with a warp density of 41 threads / inch and a weft density of 15 threads / inch. A polyethylene resin sheet (1 mm thick) with holes measuring 2 cm in the vertical direction and 2 cm in the horizontal direction, arranged in a grid pattern with a 1 cm gap between adjacent holes, was attached to the fabric.

[0156] [Table 1] [Table 2]

[0157] The average diameter and area of ​​the openings or recesses in the above embodiment, as well as the distances between openings and recesses, were measured by the following method. [Average diameter of opening, etc.] Nonwoven fabric was attached to black paper or a sheet, and then an image of the nonwoven fabric surface was captured using the scanning function of a copier (Fuji Xerox DocuCentre-VII C4473). The scanning conditions were set to: Color mode: Full color, Resolution: 600 dpi, Image quality: Highest quality. Image analysis of the scanned images was performed using the image processing software "Image J". Areas displayed in black in the scanned images were considered as apertures, and their average diameter and area were calculated.

[0158] [Average diameter of recesses, etc.] The recesses formed in the nonwoven fabric were colored in with a black marker, and the sheet was attached to black paper or a sheet. In this state, a scan image was captured using the same method as the method for measuring the average diameter of the openings described above. The parts displayed in black in the scan image were considered as recesses, and their average diameter and area were calculated. If the nonwoven fabric has both recesses and openings, the black parts visible through the openings are binarized in the same way as the recesses, so their average diameters can also be measured.

[0159] Wipe tests were conducted on each of the nonwoven fabrics in Examples 1 to 3, 8, 11, and 12 according to the following procedure. The evaluation results are shown in Table 3.

[0160] <Swab test> Approximately 1g of miso paste was spread evenly over a 6cm x 1.5cm area near the center of a transparent acrylic sheet (3mm thick, part number: KAC9143-1S, manufactured by Hikari Co., Ltd.) as a simulated stain. The combined mass of the acrylic sheet and the miso paste (m1) was determined beforehand. The mass of the simulated stain was then calculated from the difference between the previously determined mass of the acrylic sheet (m0) and m1.

[0161] A sample of simulated dirt was applied to an acrylic plate. This sample consisted of a nonwoven fabric measuring 10 cm in the MD direction and 6 cm in the CD direction (impregnated with 300 parts by mass of distilled water per 100 parts by mass of nonwoven fabric). This sample was attached to a plate-shaped jig (wiping area 6 cm × 6 cm), and while applying a pressure of 81 Pa to the jig, it was moved once in a predetermined direction at a speed of 10 mm / second and a distance of 100 mm. The mass of the acrylic plate after wiping (m²) was determined, and the difference between m1 and m² was taken as the mass of the wiped-off simulated dirt. From this mass, the wiping rate of the simulated dirt (the ratio of the mass of wiped-off simulated dirt to the mass of simulated dirt spread on the acrylic plate) was calculated. The wiping was also performed by moving the sample in directions parallel to the MD direction and the CD direction of the nonwoven fabric, and the difference in wiping rate depending on the wiping direction was also examined. For each sample, three samples were prepared, and the average value was calculated to evaluate the wiping performance of each sample.

[0162] [Table 3]

[0163] All of the nonwoven fabrics in the examples showed a higher wiping rate in the MD direction compared to Comparative Example 1. This is thought to be because the nonwoven fabrics in the examples all had stripe-shaped sections with different patterns arranged regularly in the MD direction, and the fiber web used was a parallel web, with the main orientation direction of the fibers being the MD direction, resulting in less stretching in the MD direction. In other words, even when the nonwoven fabric was moved in the MD direction, it was less likely to twist, making firm contact with the dirt, and the striped or patterned design including the third region is thought to have retained the dirt that came into contact with the nonwoven fabric at its openings, etc. The nonwoven fabrics in Examples 1 to 3 also showed a smaller difference in wiping rate due to differences in wiping direction compared to the nonwoven fabric in Comparative Example 1.

[0164] The nonwoven fabric of the example also showed a higher wiping efficiency in the CD direction compared to Comparative Example 2, which had a grid pattern. This is thought to be due to the presence of three or more regions with different patterns, i.e., regions with different fiber entanglement states, which improved the efficiency of dirt removal.

[0165] This embodiment includes the following aspects: (Aspect 1) A nonwoven fabric in which a first entanglement portion and a second entanglement portion are arranged in a striped pattern, The second confluence includes at least a first region and a second region, In a plan view, when the direction in which the first and second entangled portions extend continuously is defined as the X direction, and the direction perpendicular to the X direction is defined as the Y direction, the first region and the second region are repeatedly and alternately arranged in the X direction. The first entangled portion, the first region, and the second region have different patterns from each other. Nonwoven fabric. (Aspect 2) The nonwoven fabric of embodiment 1, wherein the first entangled portion is patternless, and the first region and the second region have a pattern formed by a high-density region and a low-density region. (Aspect 3) A nonwoven fabric according to embodiment 1 or 2, wherein, in a plan view, both the first entanglement portion and the second entanglement portion extend in a straight line. (Aspect 4) A nonwoven fabric in embodiment 1 or 2, wherein both the first and second entangled portions are meandering in a plan view. (Aspect 5) A nonwoven fabric in any of embodiments 1 to 4, wherein the dimensions of the first entangled portion in the Y direction are 2 mm or more and 200 mm or less. (Aspect 6) A nonwoven fabric in any of embodiments 1 to 5, wherein the dimensions of the second entangled portion in the Y direction are 2 mm or more and 200 mm or less. (Aspect 7) The second confluence further includes a third region, The third region is formed with at least one or both of a plurality of openings and recesses arranged in a linear line in the Y direction, In a plan view, the third region has dimensions of 9 mm or less in the X direction. In a plan view, the first to third regions are repeatedly formed in the order of the first region, third region, and second region in the X direction. The first region, the second region, and the third region have different patterns from each other. A nonwoven fabric according to any of the embodiments 1 to 6. (Pattern 8) The area M3 of each opening or recess formed in the third region is greater than the area M1 of each opening or recess formed in the first region and the area M2 of each opening or recess formed in the second region. Nonwoven fabric of the form of 7. (Aspect 9) The second confluence further includes a fourth region, The fourth region is formed with at least one or both of a plurality of openings and recesses arranged in a linear line in the Y direction, In a plan view, the fourth region has dimensions of 9 mm or less in the X direction. In a plan view, the first to fourth regions are repeatedly formed in the order of the first region, third region, second region, and fourth region in the X direction. The fourth region has a different pattern from the first and second regions. A nonwoven fabric according to any of the embodiments 1 to 8. (Aspect 10) The nonwoven fabric of embodiment 9, wherein the area M4 of each opening or recess formed in the fourth region is greater than the area M1 of each opening or recess formed in the first region and the area M2 of each opening or recess formed in the second region. (Aspect 11) To create a fiber web, The fiber web is placed on a support, and the fiber web is subjected to entanglement treatment by a high-pressure fluid flow. A method for producing a nonwoven fabric containing, The support has at least two types of woven structures A and B, In the support, the woven structure A and the woven structure B are band-shaped portions that extend along the direction in which the weft threads extend, and the woven structure A and the woven structure B are regularly and repeatedly formed along the direction in which the warp threads extend. The entanglement treatment of the fiber web placed on the support by a high-pressure fluid flow is carried out by injecting the high-pressure fluid flow along the direction in which the weft threads extend on the support, such that portions of the fiber web are alternately positioned where a high-pressure fluid flow is injected from two or more consecutive orifices of a nozzle, and portions where a high-pressure fluid flow is not injected. A method for manufacturing nonwoven fabrics. (Aspect 12) The aforementioned entanglement process using high-pressure fluid flow (i) By injecting a high-pressure fluid stream from a nozzle in which a group of orifices consisting of one or more orifices is provided at predetermined intervals, or (ii) This is carried out by placing a member between the fiber web and the nozzle, which has multiple holes arranged in a line along a direction perpendicular to the direction of travel of the support, and which prevents the high-pressure fluid from passing through anywhere other than the holes, and by injecting a high-pressure fluid stream from the nozzle. Method for manufacturing nonwoven fabric according to embodiment 11. (Aspect 13) In the aforementioned support, The diameters of the weft yarn a constituting the weave structure A and the weft yarn b constituting the weave structure B are different, and the weft yarn a and the weft yarn b are adjacent to each other at the boundary between the weave structure A and the weave structure B. The surface of the fabric structure A is located at a position 0.1 mm to 3.0 mm higher than the surface of the fabric structure B. A method for manufacturing a nonwoven fabric according to embodiment 11 or 12. (Aspect 14) A method for manufacturing a nonwoven fabric, wherein the weave structure A is a twill weave with 2 or more floating weft threads and 1 floating warp thread, and the weave structure B is a plain weave. (Aspect 15) In the support, a knuckle N1 is formed in which the warp threads constituting the support are suspended above three or more continuous weft threads, including the weft threads a and b. A method for manufacturing a nonwoven fabric according to any of embodiments 11 to 14. (Aspect 16) A method for manufacturing a nonwoven fabric, in which, in the support, a knuckle N2 is formed at the boundary between the support and the woven structure B on the side opposite to the side where the knuckle N1 is formed, as viewed from the woven structure A, where the warp threads constituting the support are floating on two or more consecutive weft threads including the weft threads a and b, and a knuckle N3 is formed adjacent to either side of the knuckle N2, where the warp threads are floating on two or more consecutive weft threads. (Aspect 17) A method for manufacturing a nonwoven fabric according to embodiment 16, wherein the weave structure A is a twill weave structure in which the number of floating weft threads is 2 or more and 16 or less and the number of floating warp threads is 2 or more and 16 or less, the weave structure B is a plain weave structure, and the diameter of the weft thread a is greater than the diameter of the weft thread b. [Industrial applicability]

[0166] The nonwoven fabric disclosed herein has a novel design unlike any other. Therefore, the nonwoven fabric disclosed herein is suitable for use as a sanitary product such as wipers, sanitary napkins, infant diapers, adult diapers, wet wipes, face masks, sanitary masks, filters, or poultices. The nonwoven fabric disclosed herein can be provided in which two or more regions in the second entanglement area are repeatedly and regularly arranged in the MD direction of the nonwoven fabric. In this case, even if the nonwoven fabric is moved back and forth in the MD direction on the surface of an object, twisting is less likely to occur, and the nonwoven fabric is particularly suitable for use as a wiper.

Claims

1. A nonwoven fabric in which a first entanglement portion and a second entanglement portion are arranged in a striped pattern, The second entanglement portion includes at least a first region and a second region, In a plan view, when the direction in which the first and second entangled portions extend continuously is defined as the X direction, and the direction perpendicular to the X direction is defined as the Y direction, the first region and the second region are repeatedly and alternately arranged in the X direction. The first entangled portion, the first region, and the second region have different patterns from each other. Nonwoven fabric.

2. The nonwoven fabric according to claim 1, wherein the first entangled portion is patternless, and the first region and the second region have a pattern formed by a high-density region and a low-density region.

3. The nonwoven fabric according to claim 1 or 2, wherein, in a plan view, both the first entanglement portion and the second entanglement portion extend in a straight line.

4. The nonwoven fabric according to claim 1 or 2, wherein both the first entangled portion and the second entangled portion are meandering in a plan view.

5. The nonwoven fabric according to any one of claims 1 to 4, wherein the dimension of the first entangled portion in the Y direction is 2 mm or more and 200 mm or less.

6. The nonwoven fabric according to any one of claims 1 to 5, wherein the dimension of the second entangled portion in the Y direction is 2 mm or more and 200 mm or less.

7. The second confluence further includes a third region, The third region is formed with at least one or both of a plurality of openings and recesses arranged in a linear line in the Y direction, In a plan view, the third region has dimensions of 9 mm or less in the X direction. In a plan view, the first to third regions are repeatedly formed in the order of the first region, the third region, and the second region in the X direction. The first region, the second region, and the third region have different patterns from each other. The nonwoven fabric according to any one of claims 1 to 6.

8. The area M3 of each opening or recess formed in the third region is greater than the area M1 of each opening or recess formed in the first region and the area M2 of each opening or recess formed in the second region. The nonwoven fabric according to claim 7.

9. The second confluence further includes a fourth region, The fourth region is formed with at least one or both of a plurality of openings and recesses arranged in a linear line in the Y direction, In a plan view, the fourth region has dimensions of 9 mm or less in the X direction. In a plan view, the first to fourth regions are repeatedly formed in the order of the first region, third region, second region, and fourth region in the X direction. The fourth region has a pattern different from that of the first and second regions. The nonwoven fabric according to claim 7 or 8.

10. The area M4 of each opening or recess formed in the fourth region is greater than the area M1 of each opening or recess formed in the first region and the area M2 of each opening or recess formed in the second region. The nonwoven fabric according to claim 9.

11. To create a fiber web, The fiber web is placed on a support, and the fiber web is subjected to entanglement treatment by a high-pressure fluid flow. A method for producing a nonwoven fabric containing, The support has at least two types of weave structures A and B, In the support, the woven structure A and the woven structure B are band-shaped portions that extend along the direction in which the weft threads extend, and the woven structure A and the woven structure B are regularly and repeatedly formed along the direction in which the warp threads extend. The entanglement treatment of the fiber web placed on the support by a high-pressure fluid flow is carried out by injecting the high-pressure fluid flow along the direction in which the weft threads extend on the support, such that portions of the fiber web are alternately positioned where a high-pressure fluid flow is injected from two or more consecutive orifices of a nozzle, and portions where a high-pressure fluid flow is not injected. A method for manufacturing nonwoven fabrics.

12. The aforementioned entanglement process using high-pressure fluid flow (i) By injecting a high-pressure fluid stream from a nozzle in which a group of orifices consisting of one or more orifices is provided at predetermined intervals, or (ii) A member having multiple holes arranged in a line along a direction perpendicular to the direction of travel of the support, and which prevents the high-pressure fluid from passing through areas other than the holes, is placed between the fiber web and the nozzle, and the high-pressure fluid stream is injected from the nozzle. A method for producing a nonwoven fabric according to claim 11.

13. In the aforementioned support, The diameters of the weft yarn a constituting the weave structure A and the weft yarn b constituting the weave structure B are different, and the weft yarn a and the weft yarn b are adjacent to each other at the boundary between the weave structure A and the weave structure B. The surface of the woven structure A is located at a position 0.1 mm to 3.0 mm higher than the surface of the woven structure B. A method for producing a nonwoven fabric according to claim 11 or 12.

14. A method for manufacturing a nonwoven fabric according to any one of claims 11 to 13, wherein the weft structure A is a twill weave structure in which the number of floating weft threads is 2 or more and the number of floating warp threads is 1, and the weft structure B is a plain weave structure.

15. In the support, a knuckle N1 is formed in which the warp threads constituting the support are suspended above three or more continuous weft threads, including the weft threads a and b. A method for manufacturing a nonwoven fabric according to claim 13 or claim 14, which references claim 13.

16. The method for manufacturing a nonwoven fabric according to claim 15, wherein in the support, a knuckle N2 is formed at the boundary between the woven structure A and the woven structure B on the side opposite to the side where the knuckle N1 is formed, with respect to the woven structure A, in which the warp threads constituting the support are floating on two or more consecutive weft threads including the weft threads a and b, and adjacent to either side of the knuckle N2, a knuckle N3 is formed in which the warp threads are floating on two or more consecutive weft threads.

17. The method for manufacturing a nonwoven fabric according to claim 16, wherein the weave structure A is a twill weave structure in which the number of floating weft threads is 2 or more and 16 or less and the number of floating warp threads is 2 or more and 16 or less, the weave structure B is a plain weave structure, and the diameter of the weft thread a is greater than the diameter of the weft thread b.

Images