JP6080319B2 - Nonwoven fabric, method for producing the same, and wiping material - Google Patents

Description

  The present invention relates to a nonwoven fabric, a method for producing the same, and a wiping material.

  Conventionally, in order to give various functions to a nonwoven fabric, a nonwoven fabric provided with a pattern or the like according to the application has been proposed. Patent Document 1 discloses a nonwoven fabric that is used for, for example, a bandage and has a large number of apertures formed on almost the entire surface. A large number of openings of various sizes and / or shapes are mixed in these many openings so that body fluids and the like are difficult to pass through. Patent Document 2 discloses a non-woven fabric that has been devised to improve its function as a wiping material, for example. In this non-woven fabric, there are alternately open rows and non-open rows in which through holes are continuously connected.

JP-A-63-182460 JP 2000-45161 A

  In general, the stress required to stretch a nonwoven fabric by 10% (hereinafter abbreviated as “10% elongation stress”) is applied to the nonwoven fabric when the nonwoven fabric is taken out of, for example, a soft packaging body or a plastic bottle-shaped packaging body. It is thought to correspond to stress. Regarding the nonwoven fabric, the stress at 10% elongation is a physical property value that is very important. If the stress at 10% elongation is small, the nonwoven fabric is stretched when the nonwoven fabric is taken out from the package, and the pattern is deformed. The effect may not be fully demonstrated.

  The nonwoven fabric disclosed in Patent Document 1 tends to have a 10% elongation stress that is smaller than that of a so-called plain nonwoven fabric that does not have, for example, the same basis weight. Therefore, the nonwoven fabric disclosed in Patent Document 1 is easier to stretch than the plain nonwoven fabric when the nonwoven fabric is taken out from the package, and the shape of the opening is likely to change from the intended shape. The intended function may not be fully demonstrated.

  About the nonwoven fabric disclosed by patent document 2, the row | line | column number of the hole in an aperture row is about n = 1-4, and the width | variety of an aperture row is narrow. Therefore, it cannot be said that the improvement in performance such as the design property and wiping property brought about by forming the aperture row is sufficient.

  As described above, it is the actual situation that a nonwoven fabric having a good strength characteristic like a plain nonwoven fabric is not obtained while having a high design property.

  In this invention, the nonwoven fabric which has high designability and favorable intensity | strength characteristics, its manufacturing method, and the wiping material using the said nonwoven fabric are provided.

  The non-woven fabric of the present invention comprises a plurality of stripes each having a regular pattern and spaced apart from each other, wherein a part of the constituent fibers of the fiber web in which the constituent fibers are entangled are rearranged by hydroentanglement. By having, it has a stripe pattern, and the width of the stripe is 4 mm to 50 mm.

  In the method for producing a nonwoven fabric of the present invention, the constituent fibers of the fiber web are entangled (first entangled), and then a part of the constituent fibers of the fiber web is subjected to water flow on a predetermined support having a regular pattern. Including a step of forming a stripe pattern by rearranging a part of the constituent fibers by entanglement and expressing a plurality of stripes having a regular pattern, wherein each stripe has a width of 4 mm to 50 mm is there.

  The wiping material of the present invention includes the nonwoven fabric of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the wiping material using the nonwoven fabric which has high designability and favorable intensity | strength and its manufacturing method, and the said nonwoven fabric can be provided.

Drawing 1 is a key map showing an example of the nonwoven fabric of the present invention. FIG. 2 is a conceptual diagram showing another example of the nonwoven fabric of the present invention. FIG. 3 is an enlarged schematic view of another example of the nonwoven fabric of the present invention. FIG. 4 is an enlarged schematic view of another example of the nonwoven fabric of the present invention. FIG. 5 is an enlarged schematic view of another example of the nonwoven fabric of the present invention. FIG. 6 is an enlarged schematic view of another example of the nonwoven fabric of the present invention. FIG. 7 is a conceptual diagram of another example of the nonwoven fabric of the present invention. FIG. 8 is a conceptual diagram of another example of the nonwoven fabric of the present invention. FIG. 9 is a schematic view of an example of a support used for producing the nonwoven fabric of the present invention. FIG. 10 is a schematic view of an example of a support used for producing the nonwoven fabric of the present invention.

  In the present invention, a stripe is a structural unit constituting a stripe pattern. In the nonwoven fabric of the present invention, the width of a stripe having a regular pattern formed by rearranging a part of the constituent fibers by hydroentanglement (hereinafter sometimes simply referred to as “stripe A”). It needs to be 4 mm to 50 mm. If the width of the stripe A is less than 4 mm or exceeds 50 mm, the effect of improving the design property becomes insufficient. Further, when the width of the stripe A exceeds 50 mm, the stress at 10% elongation is lowered. In order to obtain high designability, it is preferable that the interval between the adjacent stripes A, that is, the width of the stripe B adjacent to the stripe A is also 4 mm to 50 mm. The stripe B may be a so-called plain color or may have a pattern different from the pattern of the stripe A.

  In this case, a plain nonwoven fabric is a nonwoven fabric other than the nonwoven fabric intentionally provided with the pattern. However, nozzle lines and texture irregularities that are inevitable in production are distinguished from the pattern of the present invention and fall into the plain category. Specifically, when the design is not felt by the naked eye, more specifically, when the longest part is measured with respect to convex portions, concave portions, openings, etc., the length is 0.2 mm or less Falls into the plain category. In addition, even if it has a color pattern, it is plain when it does not have a pattern formed by rearranging some of the constituent fibers by hydroentanglement.

  In the nonwoven fabric of the present invention, the width of each stripe A and each stripe B is more preferably 5 mm to 35 mm, and further preferably 5 mm to 24 mm. When the width of each stripe A and each stripe B is 5 mm to 24 mm, not only the stress at 10% elongation in the MD direction (longitudinal direction) but also the stress at 10% elongation in the CD direction (lateral direction) is almost the entire surface. Since the nonwoven fabric tends to be larger than the nonwoven fabric in which a large number of patterns such as holes (the same pattern as the stripe A) are formed, a nonwoven fabric having both high design properties and better strength properties can be provided. Therefore, since the non-woven fabric is slightly pulled by the human hand in the MD direction or the CD direction and is stretched by 0 to 10%, the handleability is good.

  The width of the stripe A and the width of the stripe B do not have to be the same and may be different. Further, the widths of the plurality of stripes A do not have to be the same. The widths of the plurality of stripes B do not have to be the same. The width of the plurality of stripes of the nonwoven fabric of the present invention may gradually increase along the CD direction (lateral direction) or MD direction (longitudinal direction) of the nonwoven fabric in order to enhance the design of the nonwoven fabric.

  In addition, for example, as shown in FIG. 7, in the stripe pattern of an example of the nonwoven fabric of the present invention, the repeating unit in which the width of the plurality of stripes A sequentially increases in the direction orthogonal to the longitudinal direction is a plurality of times. It may be repeated. Regarding the widths of the plurality of stripes B, a repeating unit that sequentially increases in the direction orthogonal to the longitudinal direction may be repeated a plurality of times. When the nonwoven fabric is used as a wiping material, the particle size of dust that is easily captured and the type of dust are different depending on the width of the stripe A. Therefore, when the nonwoven fabric has the stripe A having a different width as described above, Various types of dust can be collected, which is preferable.

  In addition, with conventional wiping materials that have a solid surface or a large number of openings formed on the entire surface, dust is concentrated at the edge of the surface of the wiping material that contacts the surface to be wiped. Therefore, the central part of the surface of the wiping material that contacts the surface to be wiped cannot be used effectively for wiping. However, in the example of the nonwoven fabric of the present invention, the stripe pattern is one in which a repeating unit in which the width of the plurality of stripes A sequentially increases in the direction orthogonal to the longitudinal direction is repeated a plurality of times. The dust collecting ability at the center of the surface in contact with the surface to be wiped of the nonwoven fabric is higher than that of the conventional nonwoven fabric wiping material.

  As described above, when the stripe width is different, the particle diameter and the kind of dust that are easily captured are different. Therefore, the dust that was not captured by the stripe located at the edge of the surface of the wiping material that is in contact with the surface to be wiped, such as the floor, enters inside the edge and is inside the stripe located at the edge. Dust that is captured by a stripe having a different width and that is not captured by this stripe is captured by a stripe having a different width that is located further inside. Therefore, an example of the nonwoven fabric of the present invention in which the repeating unit in which the stripe pattern has a repeating unit in which the width of the stripe A gradually increases in the direction orthogonal to the longitudinal direction is repeated a plurality of times is the width of the plurality of stripes A. Dust collection ability is better than non-woven fabrics with equal.

  Moreover, as long as the nonwoven fabric of this invention has a stripe pattern by having multiple stripe A with a width of 4 mm-50 mm, and the effect of this invention is not impaired, as shown in FIG. Stripe C, which is formed by re-arranging some of the constituent fibers by hydroentanglement on the plurality of stripes constituting the pattern, has the same pattern as stripe A, and has a width of less than 4 mm or more than 50 mm May be included. The stripe C having a width of less than 4 mm or more than 50 mm may have the same pattern as the stripe A. Specifically, for example, the stress at 10% elongation in the MD direction (longitudinal direction) is larger than that of the non-woven fabric in which the same pattern as the stripe A is formed on almost the entire surface, preferably in the MD direction (longitudinal direction). ) And 10% elongation stress in the CD direction (longitudinal direction) are larger than those of the non-woven fabric in which the same pattern as the stripe A is formed on almost the entire surface, a plurality of stripe patterns are formed. The stripe C may be included in the stripe. In that case, the number of stripes A is equal to or greater than the number of stripes C.

  The longitudinal direction of the stripe in the nonwoven fabric of the present invention may be parallel to either the MD direction or the CD direction as long as sufficient 10% elongation stress is ensured, but is parallel to the MD direction. And preferred. Usually, the tension in the MD direction is applied to the fiber web during the manufacturing process of the nonwoven fabric. Therefore, when the stripe is formed along the MD direction, a desired pattern can be stably formed.

  The ratio of the thickness of the stripe A to the thickness of the stripe B (the thickness of the stripe A / the thickness of the stripe B) is preferably 1.03 or more because the dust collection performance is further improved when the value is large. 1.08 or more, more preferably 1.15 or more. The upper limit of the ratio (thickness of stripe A / thickness of stripe B) is not particularly limited, but is preferably 4.0 or less, more preferably 3.0 or less, from the viewpoint of ease of production. More preferably, it is 2.0 or less.

  In an example of the nonwoven fabric of the present invention, it is preferable that the constituent fibers include heat-sealing fibers and they are heat-sealed with adjacent fibers. In this case, the shape stability of the nonwoven fabric is improved, and a decrease in thickness due to use is also suppressed. Such a nonwoven fabric is suitable for a wiper because it is difficult to stretch. Therefore, if an example of the nonwoven fabric of the present invention in which the constituent fiber includes a heat-sealing fiber is used, a wiper that is easy to wipe and can be wiped lightly without applying force can be provided. . Such a non-woven fabric is obtained by fusing at least a part of the constituent fibers and heat-bonding the constituent fibers by heat-treating the fiber web after the step of developing stripes having a predetermined regular pattern. . The constituent fibers preferably contain 5% by mass to 40% by mass of heat-sealing fibers. When the content of the heat-fusible fiber is within the above range, it is possible to provide a non-woven fabric that has good shape stability and little fuzz and is difficult to sway.

  Examples of the structural unit constituting the regular pattern include at least one selected from the group consisting of irregularities and apertures. Examples of the pattern include a dot (circle, ellipse, triangle, polygon, etc.) pattern, a herringbone pattern, a checkered pattern, a lattice pattern, a staggered pattern, and a zigzag pattern.

  Each regular pattern has various functions and effects. For example, a dot pattern or the like in which apertures are formed at a predetermined interval contributes to improving the scraping property, and brings about an effect that it becomes difficult to stick to the skin because the contact area becomes small when contacting with the skin. In the herringbone pattern, the relatively high and low density portions of the fiber are repeated with a small period, so that a capillary phenomenon or the like is likely to occur and the water absorption of the nonwoven fabric is improved. Therefore, if a plurality of types of patterns are applied, a nonwoven fabric having a plurality of functions can be provided.

When the structural unit of the regular pattern is an aperture, if the area of the aperture and the distance w3 between apertures (see FIGS. 3 and 4) are in the following ranges, the wiping material has an excellent dust collecting property. A suitable nonwoven fabric can be provided. Preferably the area of the apertures is 0.5mm ² ~6.0mm ^2, more preferably a 3.0mm ² ~5.5mm ^2. The distance between the apertures closest to each other is preferably 1.0 mm to 3.0 mm, and more preferably 1.5 mm to 3.0 mm.

  The nonwoven fabric is not limited to a single layer, and may have a laminated structure of two or more layers including, for example, a layer mainly containing hydrophilic fibers and a layer mainly containing split-type composite fibers. If a chemical solution or the like is held in a layer mainly containing hydrophilic fibers, combined with the unique properties of split-type composite fibers, such as excellent scraping properties and flexibility, high-quality wet wipes, wet tissues, or Wet wipes such as disposable towels can be provided. In particular, when the nonwoven fabric has a laminated structure of three or more layers and includes a layer mainly containing hydrophilic fibers such as pulp as an intermediate layer, the layer mainly containing hydrophilic fibers becomes a liquid retaining layer, and the liquid is applied to the surface. Since it can be put out gradually, it is preferable. Moreover, when a layer mainly containing hydrophilic fibers such as pulp is included as an intermediate layer, the stripe pattern becomes clear, which is preferable. Here, “mainly” means that a layer mainly containing hydrophilic fibers contains 50% by mass or more of hydrophilic fibers as a main component, and a layer containing mainly split-type conjugate fibers contains split-type conjugate fibers as a main component. It means that 50 mass% or more is contained.

  In an example of the nonwoven fabric of the present invention, the stripe B in contact with the stripe A having a predetermined pattern as described above may be so-called plain or may have a regular pattern different from the pattern of the stripe A. Good. That is, the stripe pattern as an example of the nonwoven fabric of the present invention may have two or more stripes having different patterns. In this case, it is possible to provide a nonwoven fabric with more excellent design and functionality. Such a nonwoven fabric can be formed as follows, for example.

  First, the constituent fibers of the fiber web are sometimes entangled (hereinafter referred to as “first entanglement”. This first entanglement is a stripe having a regular pattern by rearranging the fibers by hydroentanglement (second entanglement). This is performed before forming the stripe pattern by forming a plurality.), And then, hydroentangling (second entanglement) of a part of the constituent fibers of the fiber web on the support having a predetermined pattern, for example, Then, a plurality of stripes A having a predetermined pattern corresponding to the pattern of the support are developed to form a stripe pattern. Next, after this step, the constituent fibers existing between the adjacent stripes A of the fiber web are hydroentangled (fourth entangled) on a support having a pattern different from the support used in the above step. A pattern different from the predetermined pattern is expressed between the stripes A. In this case, all of the constituent fibers existing between the adjacent stripes A may be hydroentangled, or some of the constituent fibers existing between the adjacent stripes A may be hydroentangled. That is, one stripe having a pattern different from the stripe A between the adjacent stripes A by making the width of the stripe formed by rearrangement of the constituent fibers by the fourth entanglement equal to the interval between the adjacent stripes A Or a single stripe having a pattern different from the stripe A, sandwiched between plain stripes, between the adjacent stripes A. May be. In this case, the width of the stripe between the plain stripes is preferably 4 to 50 mm, more preferably 5 mm to 35 mm, and further preferably 5 mm to 24 mm.

  Further, instead of hydroentanglement only the constituent fibers existing between the adjacent stripes A, the entire surface of the fiber web is hydroentangled (fifth on a support having a pattern different from the support used in the above step). Entanglement). In this case, the fifth entanglement is performed using a water flow having a lower water pressure than the high-pressure water flow used in the second entanglement so that the stripe A does not disappear due to the fifth entanglement. That is, a fiber entangled portion having a relatively regular entanglement and a predetermined regular pattern, and a fiber entangled portion having a relatively weak entanglement and a pattern different from the predetermined regular pattern, each having a predetermined width. Then, a stripe pattern is exhibited.

  Moreover, an example of the nonwoven fabric of this invention which has a some stripe which has a regular pattern, and exhibits a stripe pattern can also be manufactured by the following method (1)-(3).

  (1) First, after the first entanglement of the constituent fibers of the fiber web, a part of the constituent fibers of the fiber web is hydroentangled on the support having a predetermined pattern, for example, corresponding to the pattern of the support A plurality of stripes (stripes D) having a predetermined pattern are developed to form a stripe pattern. Next, after this step, the constituent fibers existing between the adjacent stripes D of the fiber web are hydroentangled on a support having a pattern different from the support used in the above step. At this time, a part of the stripe D is also hydroentangled. In this case, the width of the stripe consisting of the remaining portion of the stripe D that has not been hydroentangled and / or the width of the stripe between the adjacent portions of the remaining portion that has not been hydroentangled is 4 to 50 mm. If it is.

  (2) First, after the first entanglement of the constituent fibers of the fiber web, a part of the constituent fibers of the fiber web is hydroentangled on a support having a predetermined pattern, thereby corresponding to the pattern of the support, for example. A plurality of stripes (stripes D) having a predetermined pattern are developed to form a stripe pattern. Next, after this step, all of the constituent fibers constituting the stripe D are hydroentangled (sixth entanglement) on a support having a pattern different from the support used for forming the stripe D, and the constituent fibers are Rearrangement is performed to form a stripe having a different pattern from the stripe D having the same width as the stripe D on the stripe D. In this case, the width of the stripe D and the stripe formed on the stripe D may be 4 to 50 mm. Further, the width of the stripe formed by the rearrangement of the constituent fibers by the sixth entanglement may be smaller than the width of the stripe D. In this case, the width of the stripe formed by the rearrangement of the constituent fibers by the sixth entanglement or the remaining part of the stripe D in which the constituent fibers by the sixth entanglement are not rearranged is 4 to 50 mm. That's fine. The width of the stripe formed by the rearrangement of the constituent fibers by the sixth entanglement may be larger than the width of the stripe D, and the stripe formed by the rearrangement of the constituent fibers by the sixth entanglement completely covers the stripe D It may be formed as follows. In this case, the width of the stripe formed by the sixth entanglement may be 4 to 50 mm.

  (3) First, the constituent fibers of the fiber web are first entangled, and then the constituent fibers of the fiber web are hydroentangled on a predetermined support (first support) having a regular pattern. A typical pattern is formed on almost the entire surface of the fibrous web. Next, a part of the constituent fibers of the fiber web in which the pattern is formed on almost the entire surface is hydroentangled on a support (second support) different from the predetermined support (first support). By rearranging, the regular pattern in the part is erased, and a plurality of plain stripes are developed. When forming a plurality of plain stripes, the distance between adjacent plain stripes is set to 4 mm to 50 mm. Even in such a method, a part of the constituent fiber of the fiber web entangled with the constituent fibers is rearranged by hydroentanglement, each having a regular pattern and a plurality of stripes separated from each other. And the nonwoven fabric whose width | variety of each stripe is 4 mm-50 mm can be manufactured.

  In an example of the method for producing a nonwoven fabric of the present invention, hydroentanglement is performed by high-pressure water streams ejected from a plurality of orifices formed in a nozzle. In this case, if the hole diameter of the orifice is 0.05 to 0.3 mm, and the distance between the orifice and the fiber web is 7 mm to 30 mm, more preferably 6 to 20 mm, the uniformity of the texture of the nonwoven fabric is good. And a stripe having a clear pattern can be formed. The plurality of orifices are divided into a plurality of groups, and the length in the longitudinal direction of each group (for example, the length in the same direction as the CD direction) is suitably 4 to 50 mm, and is 5 to 35 mm. This is more preferably 5 to 24 mm. Further, the distance between adjacent groups is suitably 4 to 50 mm, preferably 5 to 35 mm, and more preferably 5 to 24 mm.

  Hereinafter, an example of the present invention will be described in more detail.

  The schematic diagram of an example of the nonwoven fabric of this invention is shown in FIG. 1 and FIG. The nonwoven fabric 1 shown in FIG. 1 exhibits a stripe pattern by alternately arranging plain stripes 2 and stripes 3 having a regular pattern. The nonwoven fabric 10 shown in FIG. 2 has stripes 30a having a regular pattern and stripes 30b having a different regular pattern different from the predetermined pattern alternately arranged as a whole. It has a stripe pattern.

  The nonwoven fabric 1 shown in FIG. 1 can be produced, for example, as follows. First, the constituent fibers of the fiber web are first entangled. Next, after the fiber web is arranged on a support having a predetermined pattern (pattern), a high-pressure water stream is jetted onto a part of the fiber web, and the constituent fibers of the part are secondly entangled and the constituent fibers Are rearranged to form a stripe pattern. The portion of the fibrous web that has received the high-pressure water stream becomes a stripe 3 having a regular pattern.

  The nonwoven fabric 10 shown in FIG. 2 can be produced as follows, for example. The stripe 30a can be formed in the same manner as the stripe 3 having the regular pattern shown in FIG. After arranging the non-woven fabric on which the stripe 30a is formed on a support having a pattern (pattern) different from the predetermined support used for forming the stripe 30a, a place other than the portion on which the non-woven fabric stripe 30a is formed, That is, a high-pressure water stream is sprayed only on the plain portion, and the constituent fibers of the portion are entangled (fourth entanglement) and the constituent fibers are rearranged. If it does in this way, the nonwoven fabric which has 2 or more types of stripes from which a pattern mutually differs can be produced. That is, the regular pattern which the stripe 30a has by carrying out the hydroentanglement (4th entanglement) on the support body which has the pattern different from the said predetermined support body for the constituent fiber which exists between the stripes 30a of a fiber web, A non-woven fabric having two or more stripes can be produced by expressing different patterns between the stripes 30a.

  After forming a predetermined pattern with a high-pressure water flow on the entire surface of the fiber web during the first entanglement, or on the entire surface of the plain fiber web obtained by the first entanglement Is used to form a predetermined pattern by high-pressure water flow (sometimes referred to as “third entanglement”), and then, using a support different from the support used to form this pattern, A stripe pattern may be formed by entanglement). That is, after the first entanglement and before the second entanglement, the third entanglement may be performed to form a pattern on the entire surface of the fiber web, and then the stripe pattern may be formed by the second entanglement. Alternatively, after the first entanglement of the constituent fibers of the fiber web, a pattern is formed on the entire surface thereof, and then the fiber web is placed on a support having a predetermined pattern (pattern), and then a part of the fiber web Alternatively, a stripe pattern may be formed by injecting a high-pressure water flow and entanglement (second entanglement) of constituent fibers of the portion.

  Although there is no restriction | limiting in particular about the form of a support body, What is used widely, such as the pattern net formed by weaving a monofilament or a metal wire, the roll provided with the protrusion, can be used arbitrarily. Specific examples include pattern nets such as plain weave, cedar weave, twill weave, and spiral weave, aperture plates, aperture rolls, and the like.

  As shown in FIG. 1 or FIG. 2, an example of the nonwoven fabric of the present invention has a longitudinal direction that is the same as the MD direction, a plurality of stripes having a predetermined width and a regular pattern. Since it has a stripe pattern, the design is excellent. Furthermore, since the width w1 of the stripe A having a regular pattern is 4 mm to 20 mm, as shown in the results of Examples described later, the nonwoven fabric (stripes A having a large number of patterns such as holes formed on the entire surface) The 10% elongation stress in the MD direction is larger than the non-woven fabric in which the same pattern as the above pattern is formed on the entire surface. When the width w1 of the stripe is 4 mm to 20 mm, not only the stress at 10% elongation in the MD direction but also the 10% elongation stress in the CD direction is a nonwoven fabric in which a large number of patterns such as holes are formed on the entire surface. It is larger than that of the non-woven fabric in which the same pattern as that of the stripe A is formed on the entire surface. Furthermore, the reason for this is not clear, but when the stripe width w1 is 5 mm to 15 mm, the stress at 10% elongation in the CD direction is larger than that of the plain nonwoven fabric, so that high designability and further better A non-woven fabric having both strength characteristics can be provided.

  As described above, it is not clear why the 10% elongation stress increases in the nonwoven fabric of the present invention. However, in the manufacturing process, a part of the constituent fibers are entangled again by the water flow in a relatively wide part of 4 mm to 20 mm and re-entrained. Since it is arranged, the strength of the wide portion (stripe) in which the constituent fibers are rearranged is increased, and as a result, it is presumed that the initial strength of the whole nonwoven fabric (when stretched 0 to 10%) is improved.

  In the example shown in FIG. 1, the width w2 of the plain stripe 2 is equal to the width w1 of the stripe 3 having a regular pattern, but as long as the width w1 of the stripe 3 is 4 mm to 50 mm, the nonwoven fabric of the present invention. Is not limited to this.

  As described above, the structural unit of the regular pattern includes at least one selected from the group consisting of irregularities and apertures. Although there is no restriction | limiting in particular about the aspect of a pattern, For example, a dot pattern (for example, refer FIG. 3, FIG. 4) obtained by forming many at least 1 sort (s) chosen from the group which consists of an unevenness | corrugation and an aperture | open_hole, Sugiaya All patterns such as a pattern (for example, see FIG. 5), a checkered pattern, a lattice pattern, a staggered pattern, and a zigzag pattern (for example, see FIG. 6) can be mentioned.

Here, as shown in FIGS. 5 and 6, for example, there are no portions where no fiber is present when the convex portion is viewed with the naked eye, and the thickness of the convex portion 4 is T1 and the thickness T2 of the concave portion 5 is as shown in FIGS. In this case, T1 / T2 is 1.3 or more. However, if there is an opening in the recess (the area of the opening here may be 0.5 mm ² or more, or may be less than 0.5 mm ² ), the portion where the fiber is present Let T2 be the thickness. In addition, for a nonwoven fabric with large thickness unevenness (specifically, a nonwoven fabric having T1 _av10 / T2 _av10 exceeding 2; however, T1 _av10 and T2 _av10 are average values of 10 points of T1 and T2), the unevenness is T1 _{It means that av5} / _T2av5 is 1.3 or more ( _T1av5 and _T2av5 are average values of five points of T1 and T2).

  T1 and T2 are measured using an electron microscope from a cross section obtained by cutting a nonwoven fabric in the thickness direction with a razor. Non-woven fabric fluff is not considered when determining the thickness.

For example, as shown in FIG. 3 and FIG. 4, the opening 6 is a through-hole having a part where no fiber exists from the front surface to the back surface of the nonwoven fabric, and can be seen with the naked eye. If the area is 0.5 mm ² or more, it is regarded as an open hole.

  As shown in FIG. 6, the zigzag pattern is a pattern formed by connecting the convex and concave portions of the above-described irregularities like a ridge, and further, the ridge is formed by zigzag periodically changing the angle. .

  For example, when the pattern is a dot pattern in which a large number of apertures are arranged in a staggered pattern (see FIG. 4), the dust that has passed without being captured by the apertures in the front row can be captured in the rear row in the wiping direction. Therefore, a nonwoven fabric excellent in wiping property can be obtained. Such a dot pattern can be easily obtained by using, for example, a plain weave net in which the knuckle portions are arranged in a zigzag pattern or a plate-like body having a plurality of projections arranged in a zigzag pattern as the support.

  For example, when the pattern is a herringbone pattern, a relatively high fiber portion and a low fiber portion are repeated with a small period, so that a nonwoven fabric excellent in water absorption utilizing a capillary phenomenon can be obtained. Moreover, since the unevenness | corrugations run in the diagonal direction, at the time of wiping off, dust can be taken in to the center part of the wiping surface more, and dust can be caught by the whole wiping surface, and it is preferable. The cedar pattern can be easily obtained, for example, by using a twill net as a support.

  For example, as shown in FIG. 5, in the herringbone pattern, a line a that is inclined at a predetermined angle with respect to the MD direction and a line b that is symmetrical to the line a are alternately repeated along the CD direction. It is. In this case, it is preferable that the predetermined angle [theta] is 5 to 60 [deg.], Since dust collecting properties and slipping properties when a non-woven fabric is used as a wiping cloth are improved.

  For example, when the pattern is a zigzag pattern, for example, as shown in FIG. 6, if the height of the convex part 4 of the zigzag pattern is increased, a relatively large amount of water or chemicals can be stored in the convex part 4. This is preferable. The zigzag pattern can be easily obtained by using, for example, a plain weave net with two warps as a support, or a punching plate with a zigzag pattern.

  Although there is no restriction | limiting in particular about the shape of an opening, For example, circular shape, an ellipse shape, a rectangular shape, a rhombus shape etc. are mentioned. For example, when the regular pattern is formed from a plurality of openings, the sizes of the openings may be the same or different. It is preferable that the sizes of the apertures are different because they can catch dirt of various sizes.

  The shape of the constituent fiber of the fiber web used for the production of the nonwoven fabric of the present invention is not particularly limited, and examples thereof include a single fiber, a sheath-core type composite fiber, a split type composite fiber, or a fiber having an irregular cross section.

  The material of the constituent fibers of the fibrous web includes one or more materials. When the constituent fibers are made of two or more kinds of materials (when the fiber web is made of one kind of constituent fibers and the constituent fibers themselves are made of two or more kinds of materials, and the fiber web is made of two or more kinds of constituent fibers having different materials. When at least one of the two or more materials includes a material having a relatively lower melting point than the other materials, the structure is maintained while maintaining a regular pattern. The fibers can be fused, which is preferable.

  The fineness of the constituent fibers is preferably 0.1 dtex or more and 6.6 dtex or less, and more preferably 0.25 dtex or more and 3.3 dtex or less, because a clear pattern can be formed without adversely affecting the fibers.

  Examples of the constituent fiber material include natural fibers such as cotton, silk, and pulp, regenerated fibers such as rayon (solvent spinning type and viscose rayon), acetate, acrylic resin, polyamide such as nylon 6 and nylon 66, Examples thereof include polyesters such as polyethylene terephthalate and polybutylene terephthalate, and polyolefins such as polyethylene and polypropylene.

  When using the nonwoven fabric of the present invention as a wiping material, depending on the use of the wiping material, the type and fineness of the fiber to be used, the basis weight of the nonwoven fabric, etc. may be set as appropriate, for example, the nonwoven fabric of the present invention is fine dust, When used as dry wipes such as flooring wipers and precision wipers for the purpose of wiping off dust etc., the nonwoven fabric consists of two components that are incompatible, and at least one component is at least two in the fiber cross section. It is preferable to contain 50% by mass or more of split-type composite fibers that are divided into two, more preferably 70% by mass or more. Examples of the combination of the two components include nylon / polyester, polyester / polypropylene, ethylene-vinyl alcohol copolymer / polypropylene, and polyester / polyethylene. The fineness of these fibers is preferably 3.5 dtex or less for the reason that wiping property is good and the liquid entanglement property is good and the hydroentanglement property is good and the pattern tends to appear.

  Examples of the fibers contained in the nonwoven fabric in addition to the split type composite fibers include synthetic fibers composed of a single component. Among them, polyester fibers and rayon fibers having a fineness of 6.6 dtex or less are preferable.

  Examples of the fibrous web include a card web, an air laid web, a wet paper web, a long fiber web (for example, a spunbond web), a meltblown web, and the like, and are not particularly limited as long as the web can be rearranged by hydroentanglement.

  When the use of the nonwoven fabric of the present invention is a wet wiper such as wet wiper, wet tissue, or disposable towel, etc., the nonwoven fabric may be natural fibers such as cotton, silk, pulp, rayon (solvent spinning type or screw). It is preferable to contain regenerated fibers such as coarse rayon), semi-synthetic fibers such as acetate, and hydrophilic fibers such as acrylic fibers. In particular, when the hydrophilic fiber contains at least one cellulose fiber selected from the group consisting of rayon, pulp, and cotton, for example, the synthetic fiber is equivalent to a non-woven fabric having no or no water absorption, such as polyester or polypropylene. The nonwoven fabric has a higher water absorption and has a larger 10% elongation stress, which is preferable. The constituent fibers preferably contain 30% by mass or more of hydrophilic fibers, and more preferably contain 50% by mass or more. The inclusion of hydrophilic fibers is also preferable in that a clear pattern is easily formed. The upper limit of the content of the hydrophilic fiber is preferably 90% by mass or less because the sufficient breaking strength is ensured.

The basis weight of the first entangled fiber web is preferably 20 to 300 g / m ² , and more preferably ²⁰ to 100 g / m ² because a clear pattern can be formed.

  The first entanglement of the fiber web may be performed by any method such as a needle punching method, a hydroentanglement method, and an embossing method from the viewpoint of productivity. However, a part of the constituent fibers is rearranged by hydroentanglement. And since the 2nd entanglement performed in order to form a stripe pattern is performed by the hydroentanglement method, it is preferable when it is performed by the hydroentanglement method.

  When the first entanglement is performed by hydroentanglement, the form of the support used at that time is not particularly limited, and a conventionally known support may be used. For example, the warp wire diameter is 0. A plain weave net having a size of 05 mm to 1.5 mm, a weft wire diameter of 0.05 mm to 1.5 mm, and a mesh number of 15 to 110 mesh is suitable. In order to obtain a plain fiber web by the first entanglement, for example, the warp wire diameter is 0.05 mm to 0.2 mm, the weft wire diameter is 0.05 mm to 0.2 mm, and the number of meshes is 70 to 110 mesh. It is preferable to use a plain weave net.

  The pressure of the water flow used when rearranging the constituent fibers of the fiber web (the set value of the water feeder, hereinafter the same for any water flow pressure) is usually preferably 1 to 14 MPa, and preferably 2 to 10 MPa. Is more preferable.

For example, when processing a fiber web of 20 to 300 g / m ² , the pressure of the water flow when performing the first entanglement is preferably 1 to 12 MPa from the viewpoint of improving the entanglement property of the fibers and the entanglement uniformity. ˜9 MPa is more preferable.

When the third entanglement is performed in the manufacturing process of an example of the nonwoven fabric of the present invention, the water flow pressure when performing the third entanglement may be set according to the basis weight of the fiber web to be processed, the pattern to be formed, and the like. However, when processing a fiber web of 20-300 g / m < ² >, for example, 1-14 MPa is preferable and 2-10 MPa is more preferable.

  As above-mentioned, in an example of the manufacturing method of the nonwoven fabric of this invention, a high voltage | pressure water flow is injected with respect to a part of 1st entangled and / or 3rd entangled fiber web. The jet of the high-pressure water stream is performed under such a condition that the constituent fibers of the fiber web are rearranged to form holes or irregularities in the nonwoven fabric.

When the second entanglement is performed in the manufacturing process of an example of the nonwoven fabric of the present invention, the water flow pressure when performing the second entanglement may be set according to the basis weight of the fiber web to be processed, the pattern to be formed, and the like. However, for example, when processing a fiber web of 20 to 300 g / m ² , 1 to 14 MPa is preferable and 2 to 10 MPa is more preferable because a clear pattern can be formed without damaging the support.

When the fourth entanglement is performed in the manufacturing process of an example of the nonwoven fabric of the present invention, the water flow pressure when performing the fourth entanglement may be set according to the basis weight of the fiber web to be processed, the pattern to be formed, and the like. However, when processing a fiber web of 20-300 g / m < ² >, for example, 1-14 MPa is preferable and 2-10 MPa is more preferable.

When the fifth entanglement is performed in the manufacturing process of an example of the nonwoven fabric of the present invention, the pressure of the water flow when performing the fifth entanglement may be set according to the basis weight of the fiber web to be processed, the pattern to be formed, or the like. However, when processing a fiber web of 20-300 g / m < ² >, for example, 1-12 MPa is preferable and 2-9 MPa is more preferable.

When the sixth entanglement is performed in the manufacturing process of an example of the nonwoven fabric of the present invention, the water flow pressure when performing the sixth entanglement may be set according to the basis weight of the fiber web to be processed, the pattern to be formed, or the like. However, when processing a fiber web of 20-300 g / m < ² >, for example, 1-14 MPa is preferable and 2-10 MPa is more preferable.

  For supplying the high-pressure water stream, for example, one or more nozzles that are arranged so that the longitudinal direction thereof is orthogonal to the traveling direction of the fibrous web and have a plurality of orifices (openings) can be used. The diameter of the orifice is preferably 0.05 mm or more from the reason that a clear pattern can be formed, and 0.5 mm or less from the reason that the texture can be adjusted without disturbing the fiber web. preferable. The interval between adjacent orifices is suitably 0.3 mm to 1.5 mm.

  The positions where the orifices are formed in the nozzle, the interval between adjacent orifices, and the like are appropriately set according to the pattern formed on the fiber web, but the plurality of orifices are formed in a plurality of groups. An appropriate distance between adjacent groups is 5 to 50 mm. In addition, it is preferable that the distance between adjacent orifices in each group is 0.3 to 1.5 mm because a pattern can be clearly displayed.

  Further, the distance between the orifice and the fiber web is preferably 7 to 30 mm, more preferably 10 to 25 mm because a clear pattern can be formed.

  Hereinafter, the contents of the present invention will be described with reference to examples. The thickness, breaking strength, breaking elongation, 10% elongation stress, hole area, and distance between adjacent holes of the obtained nonwoven fabric were measured as follows. The ratio (thickness of stripe A (patterned portion) / thickness of stripe B (plain portion)) was obtained as follows.

[Thickness]
Using a nonwoven fabric thickness measuring machine (trade name: THICKNESS GAUGE model CR-60A, manufactured by Daiei Kagaku Seiki Seisakusho Co., Ltd.), the measurement was performed in accordance with JIS L 1096 with a load of 3 g per 1 cm ^{2 of} the sample.

[Strength at break, elongation at break]
In accordance with JIS L 1096, a sample piece having a width of 5 cm and a length of 15 cm is gripped so that the chuck spacing is 10 cm, and a constant speed extension type tensile tester (trade name: Tensilon UCT-1T manufactured by Orientec Co., Ltd.) is used. The sample piece was stretched at a tensile speed of 30 cm / min, and the load value and elongation rate at break were measured as the breaking strength and breaking elongation, respectively.

[10% elongation stress]
When the 10% elongation is applied, the load value at the time of 10% elongation at the time of breaking strength measurement, that is, the load value when the measurement is started by 1 cm (the load value when the distance between chucks (10 cm) becomes 11 cm) Measured as stress.

[Aperture area]
Under an environment where the temperature and humidity are kept constant, the surface of the nonwoven fabric is magnified using a stereomicroscope (trade name: SZX12 manufactured by Olympus Corporation) (magnification 50 times), and the resulting image is printed on plain paper. And the part corresponding to arbitrary five openings was cut out from the said plain paper. The aperture area was calculated from the basis weight (mass per unit area) of the cut out plain paper, and the average value of these values was divided by the observed magnification to obtain the aperture area.

[Distance between adjacent holes]
Using a stereomicroscope (trade name: SZX12, manufactured by Olympus Corporation), the surface of the non-woven fabric was magnified (magnification 50 times), and the distance between adjacent holes was measured with a ruler from the obtained image, and the average value was calculated. The distance between adjacent apertures was calculated by dividing by the observed magnification. However, the distance between the openings was the distance between the centers of the adjacent openings.

[Ratio (thickness of stripe A / thickness of stripe B)]
A non-woven fabric was cut into stripes A (parts with patterns) and stripes B (solid parts) arranged between adjacent stripes A, and the thickness of five layers each was measured according to JIS L 1096. The measurement was performed with a load of 3 g per 1 cm ² . For the measurement, a non-woven fabric thickness measuring device (trade name: THICKNESS GAUGE model CR-60A, manufactured by Daiei Scientific Instruments Co., Ltd.) was used. The ratio (thickness of the stripe A / thickness of the stripe B) was determined using the thickness of the five stripes A and the thickness of the five stripes B obtained.

[Examples 1 to 12]
80% by mass of solvent-spun rayon fiber (fineness: 1.7 dtex, fiber length: 40 mm, manufactured by Lyocell Lenzing), the first component is polyethylene terephthalate (melting point: 253 ° C.), and the second component is high-density polyethylene (melting point: 132 ° C.) 10% by mass of a split-type composite fiber having a cross-sectional shape that is radially divided into eight (fineness 2.2 dtex, fiber length 51 mm, product name DFS (SH) manufactured by Daiwabo Polytech Co., Ltd.) and a sheath component of polyethylene (melting point 132 ° C. ), A core-sheath type composite fiber (fineness 2.2 dtex, fiber length 51 mm) having a core component of polypropylene (melting point: 160 ° C., trade name: NBF (H), manufactured by Daiwa Spinning Co., Ltd.), and mixed with 10% by mass was obtained. The resulting product was carded using a roller-type parallel card to produce a card web having a basis weight of 50 g / m ² .

  Next, while placing the card web on the first entanglement net and proceeding at a speed of 4 m / min, orifices with a hole diameter of 0.13 mm are provided at 0.6 mm intervals on the surface of the card web. After injecting a columnar water flow having a water pressure of 3 MPa using the water supply device, a columnar water flow having a water pressure of 2.5 MPa was injected to the back surface using the same water supply device. The distance between the surface of the card web and the orifice was 15 mm. A first entangled fiber web was obtained as described above. A plain weave PET net having a warp wire diameter of 0.132 mm, a weft wire diameter of 0.132 mm, and a mesh count of 90 mesh was used for the first interlacing net.

  Next, using the following nets A to F as a support, second entanglement was performed from the surface side of the fiber web, and a plurality of stripes having a regular pattern and parallel to the MD direction were formed. Subsequently, it dried and heat-processed in the dryer whose atmospheric temperature is 140 degreeC, and obtained the nonwoven fabric of Examples 1-12 and 16-22 shown in Table 1.

  When performing the second entanglement, the water supply unit used when performing the first entanglement was used, but some of the plurality of orifices were closed so that there was no water flow. The traveling speed was 4 m / min, the water pressure during the second entanglement was 4.5 MPa, and the distance between the surface of the fiber web and the orifice was 15 mm. The arrangement of the plurality of orifices in the water feeder is such that the width of the stripe having a regular pattern formed during the second entanglement is 6 mm, 12 mm, 24 mm, and formed during the second entanglement. The distance between stripes was set to 6 mm, 12 mm, and 24 mm.

[Net A] A plain weave net with a warp wire diameter of 0.132 mm, a weft wire diameter of 0.132 mm, and a mesh count of 25 mesh. [Net B] A warp wire diameter of 1.2 mm and a weft wire diameter of 1. Plain weave net with 2 mm, warp density 12 / inch, weft density 12 / inch [Net C] 3 with warp wire diameter 0.4 mm, weft wire diameter 0.8 mm, weave density 68/18 pieces / inch / 1 Cedar twill net [Net D] Plain weave with a warp wire diameter of 0.9 mm, a weft wire diameter of 1.0 mm, a warp density of 9 / inch, a weft density of 10 / inch, and two warps Net [Net E] Plain weave net with warp wire diameter 1.2mm, weft wire diameter 1.2mm, warp density 6.5 / inch, weft density 5.5 / inch [Net F] Warp wire Diameter 0.8mm, weft wire diameter 0.8mm, warp Degree 8.5 lines / inch, weft density 9 / inch of plain weave net
[Example 13]
A first entangled fiber web was obtained in the same manner as in Examples 1-12. Next, hydroentanglement (third entanglement) was performed from the back using the net C, and a regular pattern was formed on the entire surface of the fiber web. Next, the fiber web having a regular pattern on the entire surface was subjected to second entanglement using the net A to form a plurality of stripes parallel to the MD direction. When performing the second entanglement, the water supply unit used when performing the first entanglement and the third entanglement was used, but some orifices of the plurality of orifices were closed and used so that there was no water flow. Formed a 12 mm stripe. The water pressure when performing the third entanglement was 3.0 MPa, and the distance between the surface of the fiber web and the orifice was 15 mm. The water pressure during the second entanglement was 4.5 MPa, and the distance between the surface of the fiber web and the orifice was 15 mm. Subsequently, it dried and heat-processed in the dryer whose atmospheric temperature is 140 degreeC, and obtained the nonwoven fabric of Example 13 shown in Table 1.

[Example 14]
A nonwoven fabric of Example 14 was obtained in the same manner as in Example 5 except that the plain portion in Example 5 was 6 mm.

[Example 15]
A nonwoven fabric of Example 14 was obtained in the same manner as in Example 5 except that the plain portion in Example 5 was 24 mm.

[Comparative Example 1]
In the same manner as in Examples 1 to 12, the card web was first entangled to obtain a fiber web. Using a water supply device in which orifices with a hole diameter of 0.13 mm are provided at intervals of 0.6 mm on the nozzle on the back surface of the obtained fiber web, the columnar water flow with a water pressure of 2.5 MPa is blocked with any orifice. It sprayed to the whole surface without. The distance between the surface of the fiber web and the orifice was 15 mm. Next, as in Example 1, the nonwoven fabric of Comparative Example 1 was obtained by drying and heat treatment in a dryer having an atmospheric temperature of 140 ° C.

[Comparative Examples 2-5, 7, 8]
In the same manner as in Examples 1 to 12, the card web was first entangled to obtain a fiber web. The obtained fiber web is arranged on the nets A to F, and a water feeder in which orifices having a diameter of 0.13 mm are provided at intervals of 0.6 mm on the nozzle with respect to the entire surface of the fiber web. A columnar water flow having a water pressure of 4.5 MPa was jetted without blocking any orifice. The distance between the surface of the fiber web and the orifice was 15 mm. Subsequently, similarly to Example 1, it dried and heat-processed in the dryer whose atmospheric temperature is 140 degreeC, and obtained the nonwoven fabric of Comparative Examples 2-5, 7, and 8.

[Comparative Example 6]
A nonwoven fabric was obtained in the same manner as in Example 1 except that the width of the stripe having a regular pattern was 2 mm and the width of the plain stripe was 40 mm.

  As shown in Table 2, the nonwoven fabrics of Comparative Examples 2-5, 7, and 8 have higher MD direction breaking strength and CD direction breaking strength than the plain nonwoven fabric of Comparative Example 1, but 10 in the MD direction. % Elongation stress and 10% elongation stress in the CD direction are small. On the other hand, the nonwoven fabrics of Examples 1 to 22 not only have a higher breaking strength in the MD direction and a higher breaking strength in the CD direction than the plain nonwoven fabric, but also have the same net at 10% elongation stress in the MD direction. It is larger than that of the nonwoven fabrics of Comparative Examples 2-5, 7 and 8 in which a large number of openings were formed on the entire surface. Further, for Examples 1 to 8, 13 to 17, 19, and 20 in which the width of the stripe formed by rearranging the constituent fibers by hydroentanglement is 6 mm and 12 mm, the stress at 10% elongation in the CD direction is a comparative example. It is larger than that of 1 plain nonwoven fabric.

  From the above, it was confirmed that the nonwoven fabrics of Examples 1 to 22 were superior in design and strength characteristics in comparison with the nonwoven fabrics of Comparative Examples 2 to 5, 7, and 8. In particular, for the nonwoven fabrics of Examples 1-8, 13-17, 19, and 20, the 10% elongation stress in the CD direction is higher than that of the plain nonwoven fabric of Comparative Example 1, so that the width of the stripe is 6 mm to 12 mm. In other words, it was confirmed that a nonwoven fabric having both high design properties and better strength characteristics can be provided, and a nonwoven fabric particularly suitable for use such as wiping can be provided. Therefore, if the width of the stripe having a predetermined pattern formed by rearranging the constituent fibers by hydroentanglement is 5 mm to 15 mm, the nonwoven fabric is slightly pulled by a human hand in a direction perpendicular to the longitudinal direction of the stripe. Therefore, the handleability of the nonwoven fabric is improved.

  In addition, in the nonwoven fabrics of Examples 16 to 21 in which the stripes having a predetermined pattern were formed using the nets E and F, the convex and concave portions were connected to form a crease, and the crease was curved. An uneven pattern is observed.

[Example 23]
Solvent-spun rayon fiber (fineness 1.7 dtex, fiber length 38 mm, manufactured by Lyocell Lenzing) 60%, sheath component is polyethylene (melting point: 132 ° C), core component is polypropylene (melting point: 160 ° C, trade name: NBF (H) Daiwa Spinning Co., Ltd. The core-sheath type composite fiber (Fineness 1.7 dtex, fiber length 51 mm) 40% by mass is blended, and the resulting product is carded using a roller-type parallel card, and the basis weight is obtained. Produced a 27 g / m ² card web (upper layer).

Moreover, the same thing (lower layer) as the said card web was created. Furthermore, a tissue (weighing 17 g / m ² , manufactured by Havicks Co., Ltd.) made of 100% by mass of pulp fibers was prepared.

  The upper layer, the middle layer, and the lower layer were laminated in this order, and a columnar water flow was jetted onto the resulting three-layer laminate to obtain a first entangled fiber web. The water pressure of the columnar water flow supplied to the front surface of the card web was 3.0 MPa, and the water pressure of the columnar water flow supplied to the back surface was 3.0 MPa. The other conditions for performing the first entanglement are the same as those for producing the nonwoven fabric of Example 1.

  Next, using the following net B as a support, second entanglement was performed from the surface side of the fiber web to form a plurality of stripes having a regular pattern and parallel to the MD direction.

  The water pressure when performing the second entanglement was set to 3.0 MPa. The width of the stripe having a regular pattern formed at the time of the second entanglement is 20 mm, and the distance between the stripes formed at the time of the second entanglement (the width of the stripe B (plain portion)) is 5 mm. I did it. The distance between the surface of the fiber web and the orifice when performing the second entanglement, and the drying and heat treatment conditions performed after the second entanglement are the same as in the case of producing the nonwoven fabric of Example 1.

  In the nonwoven fabric of Example 23 produced in this way, since the water pressure at the time of the second entanglement is relatively low, no clear opening is formed, and the stripe formed by the second entanglement is not A plurality of depressions were observed, and an uneven pattern was observed.

[Comparative Example 9]
In the same manner as in Example 23, a laminate having a three-layer structure was first entangled to obtain a fiber web. A columnar water stream was sprayed on the entire surface of the fiber web on the back surface of the obtained fiber web under the same conditions as those for the production of the nonwoven fabric of Comparative Example 1. Next, as in Comparative Example 1, the nonwoven fabric of Comparative Example 9 was obtained by drying and heat treatment in a dryer having an atmospheric temperature of 140 ° C.

[Comparative Example 10]
In the same manner as in Example 23, a laminate having a three-layer structure was first entangled to obtain a fiber web. The obtained fiber web was placed on the net B, and a columnar water stream was sprayed on the entire surface of the fiber web under the same conditions as those for the production of the nonwoven fabric of Comparative Example 3. Next, as in Comparative Example 3, the nonwoven fabric of Comparative Example 10 was obtained by drying and heat treatment in a dryer having an atmospheric temperature of 140 ° C.

  As shown in Table 3, the nonwoven fabric of Comparative Example 10 (whole pattern) has a 10% elongation stress in the MD direction and a 10% elongation stress in the CD direction smaller than the nonwoven fabric of the Comparative Example 9 (whole surface plain). On the other hand, the nonwoven fabric of Example 23 has a 10% elongation stress in the CD direction larger than that of the nonwoven fabric of Comparative Example 10 (entire pattern) and the nonwoven fabric of Comparative Example 9 (entire plain). The 10% tensile stress in the MD direction of the nonwoven fabric of Example 23 is smaller than that of the nonwoven fabric of Comparative Example 9 (whole surface plain), but larger than that of the nonwoven fabric of Comparative Example 10 (whole surface pattern). Further, in the nonwoven fabric of Example 23, the net B is used for forming a stripe having a regular pattern because a tissue composed of 100% by mass of pulp fibers which are hydrophilic fibers is used as the intermediate layer. Compared to the obtained nonwoven fabrics of Examples 2, 6, and 10, the pattern formed by the second entanglement is clear.

[Examples 24-29]
The nonwoven fabrics of Examples 24 to 29 were produced by the following method. The following support (a) (net B), support (b) (spiral net), or support (c) (open metal plate) was used as the support used when performing the second entanglement. . As shown in FIG. 9, the support (b) is a spiral net made of a polyester monofilament having a spiral wire diameter of 0.92 mm, a lot wire diameter of 0.85 mm, and a lot pitch of 5 mm. . The number of spiral wires per inch is eleven. As shown in FIG. 10, the support (c) is an open metal plate having a thickness of 0.32 mm in which square holes of about 4 mm square are formed. The distance between adjacent square holes is about 1 mm. Moreover, after producing a card web as follows, the following manufacturing method (i) or manufacturing method (ii) was performed.

Polyethylene terephthalate (PET) single fiber (fineness: 1.45 dtex, fiber length: 51 mm, manufactured by Toray Industries, Inc.) 85% by mass, sheath component: polyethylene (melting point: 132 ° C.), core component: polypropylene (melting point: 160 ° C. Product name: NBF (H) Daiwa Boseki Co., Ltd.) is mixed with 15% by mass of core-sheath type composite fiber (fineness 1.7 dtex, fiber length 51 mm), and the resulting product is carded using a roller-type parallel card. A card web having a basis weight of 50 g / m ² was produced.

[Production method (i)]
A columnar water stream was jetted onto the card web to obtain a first entangled fiber web. The water pressure of the columnar water flow supplied to the front surface of the card web was 2.5 MPa, and the water pressure of the columnar water flow supplied to the back surface was 3.0 MPa. The other conditions for performing the first entanglement are the same as those for producing the nonwoven fabric of Example 1.

  Next, using the support (a), the support (b), or the support (c), the second entanglement is performed from the surface side of the fiber web, has a regular pattern, and is parallel to the MD direction. Multiple stripes were formed.

  The water pressure during the second entanglement is 2.5 MPa when the support (a) is used, 3.0 MPa when the support (b) is used, or when the support (c) is used. Was 3.5 MPa. The widths of the stripes having a regular pattern formed at the time of the second entanglement are all 12 mm, and the distance between the stripes formed at the time of the second entanglement (the width of the stripe B (plain portion)) is any Was set to 12 mm. The distance between the surface of the fiber web and the orifice when performing the second entanglement, and the drying and heat treatment conditions performed after the second entanglement are the same as in the case of producing the nonwoven fabric of Example 1.

[Production method (ii)]
A columnar water stream was jetted onto the card web to obtain a first entangled fiber web. The water pressure of the columnar water flow supplied to the surface of the card web was 2.5 MPa, and the columnar water flow was not jetted to the back surface. The other conditions for performing the first entanglement are the same as those for producing the nonwoven fabric of Example 1.

  Next, the first entangled fiber web was placed on the support (a), the support (b), or the support (c), and proceeded at a speed of 4 m / min while being first entangled. A columnar water stream was jetted onto the entire surface of the fiber web using a water supply device in which orifices having a hole diameter of 0.13 mm were provided in the nozzle at intervals of 0.6 mm. When performing this water entanglement, the water feeder used when performing the first entanglement was used. The water pressure during the hydroentanglement is 2.0 MPa when the support (a) is used, 3.0 MPa when the support (b) is used, or when the support (c) is used. Was 3.5 MPa. The distance between the surface of the fiber web and the orifice was 15 mm.

  Next, the fiber web that has been hydroentangled on the support (a), the support (b), or the support (c) is placed on the first entanglement net used in the first entanglement. Formed by jetting a columnar water flow onto the fiber web surface, parallel to the MD direction, and hydroentangled on the support (a), support (b), or support (c). A plurality of almost plain stripes were formed, although the pattern remained slightly. The water pressure of the columnar water flow was 3.5 MPa. When forming the plain stripes, the width of each plain stripe was 12 mm, and the distance between adjacent plain stripes (that is, the width of each stripe having a predetermined pattern was 12 mm).

  About the nonwoven fabric of Examples 24-29, ratio (thickness of the stripe A / thickness of the stripe B) was measured according to the above-mentioned method, and it was set as Table 3 below. As shown in Table 3, the ratio (stripe A thickness / stripe B thickness) of the non-woven fabric manufactured by using the manufacturing method (ii) is larger than that of the non-woven fabric manufactured by using the manufacturing method (i). It was.

  Moreover, in the nonwoven fabrics of Examples 24 and 25 produced by the above production method (i) using the support (a) as the support, the water pressure at the time of the second entanglement is relatively low. A plurality of depressions were observed in the stripes that were not formed but formed by the second entanglement, and uneven patterns were observed.

  In addition, the stripes having a predetermined pattern observed in the nonwoven fabrics of Examples 26 and 27 produced using the support (b) as the support were formed on the spiral line of the fiber web and lots in the manufacturing process. A concave / convex pattern similar to a herringbone pattern formed by forming a concave portion on the line and forming a convex portion on the space between adjacent spiral lines in the fiber web was observed. .

  In addition, the stripes having the predetermined pattern of Examples 28 and 29 produced using the support (c) as the support are arranged at locations corresponding to the square holes in the fiber web in the manufacturing process. The uneven | corrugated pattern formed when the done part became a convex part was observed.

  Next, about the nonwoven fabric of Examples 1-22, 24-29 and Comparative Examples 1-5, 7, and 8, the wiping characteristic was evaluated by the method shown below.

[Wiping properties]
Examples 1-22, 24-29 and Comparative Examples 1-5, 7 in which 0.50 g of JIS dust 7 types were uniformly dispersed on a glass surface in a size of 10 cm × 30 cm and masses were measured in advance. The above dust was wiped off with 8 nonwoven fabrics (length 7 cm, width 12 cm). Wiping was performed in a state where a nonwoven fabric was attached to the sponge so that the area contributing to wiping was 35 cm ² and a weight of 500 g was applied. The mass of the nonwoven fabric after two reciprocations was measured, the dust adsorption rate was calculated according to the following (formula 1), and the wiping characteristics according to the following criteria were evaluated. The results are shown in Tables 5-7.

Dust adsorption rate (%) = (mass after wiping-mass before wiping) /0.5 x 100 (Formula 1)
[Wiping property evaluation criteria]
×: Dust adsorption rate is less than 12% Δ: Dust adsorption rate is 12% to 15%
○: Dust adsorption rate is 16% to 19%
A: Dust adsorption rate is 20% or more

  As can be seen from the results shown in Tables 5 and 6, the non-woven fabric on which the stripes having a regular pattern were formed using the nets A to F had the highest dust adsorption rate when the stripe width was 12 mm. high. From this, when the width of the stripe is 10 to 15 mm, it is presumed that the dust adsorption rate is higher than that of the nonwoven fabric with the stripe width of less than 10 mm or more than 15 mm.

  Moreover, about the nonwoven fabric in which the stripe which has a regular pattern was formed using the net | network B or the net | network E, when the width | variety of a stripe is 12-24 mm, regular using net | network A, C, D, or F The dust adsorption rate is higher than that of a non-woven fabric on which stripes having different patterns are formed.

  About the nonwoven fabric in which stripes having a regular pattern are formed using the net B, the area of the opening is relatively large, and the area of the portion of the nonwoven fabric that is located in the vicinity of the opening and protrudes in the water jet direction Is big. More specifically, if the area of the opening is large, the amount of fibers pushed away to form the opening is large, and in the vicinity of the opening, the amount of the fiber is raised more than the part where the opening is not formed. It is in the state. Therefore, the level | step difference of the vicinity of the opening of a nonwoven fabric and the part in which the opening away from the opening is not formed rather than the said vicinity is large. In this way, the stripe portion having a regular pattern is lower in flatness than the plain portion, so that relatively large dust is captured by the stripe having a plurality of openings, and fine dust is captured by the plain stripe. Thus, it is presumed that the dust adsorption rate is high.

  On the other hand, since the non-woven fabric of Comparative Example 1 has a small gap for adsorbing dust, it is presumed that relatively large dust cannot be captured and the dust adsorption rate is low. About the nonwoven fabric of the comparative example 3, since the opening was formed in the whole surface using the net | network B, it is estimated that the dust capture | acquisition area is small and the dust adsorption rate is low.

  Moreover, as shown in Table 7, for Examples 24 to 29 nonwoven fabrics in which stripes (width 12 mm) having a regular pattern were formed using the supports (a) to (c), the regular pattern was used. It is considered that the dust adsorption rate is high because the stripe-like pattern having a height is a concavo-convex pattern having a relatively large step between the concave portion and the convex portion.

  The nonwoven fabric of the present invention is useful for a surface material of absorbent articles, medical materials such as gauze, table cloths, etc., and is particularly suitable for wiping materials such as precision wipers, cleaning wipers, wet wipers, and wipes. The non-woven fabric of the present invention is suitable for wet wipes such as wet wipers, wet tissues or disposable towels when the constituent fibers contain 30% by mass of hydrophilic fibers. When the nonwoven fabric of the present invention contains 50% by mass or more of a split type composite fiber made of an incompatible two-component resin and having at least one component divided into two or more in the fiber cross section, Suitable for high-performance wipes such as precision wipers.

1, 10 Nonwoven fabric 2 Plain stripe (stripe B)
3 Stripe having a predetermined pattern (stripe A)
3a Stripe C
30a Stripe having a predetermined pattern (stripe A)
30b Stripe having a predetermined pattern (stripe B)
4 Convex part 5 Concave part 6 Opening

Claims (6)

A part of the constituent fibers of the fiber web in which the constituent fibers are entangled is formed by rearrangement by hydroentanglement, each of which has a regular pattern and includes a plurality of stripes A, which are adjacent to each other. Between the stripes A, it consists of stripes having a pattern different from the stripes A and / or plain stripes, the width of the stripes A is 4 mm to 50 mm, and the structural unit of the regular pattern is uneven, A nonwoven fabric in which the regular pattern is an oblique stripe pattern.   The nonwoven fabric according to claim 1, wherein the longitudinal direction of the stripe A is parallel to the MD direction (longitudinal direction) of the nonwoven fabric.   The nonwoven fabric according to claim 1 or 2, wherein the constituent fibers include 5% by mass to 40% by mass of heat-sealed heat-sealed fibers.   The nonwoven fabric according to any one of claims 1 to 3, wherein the constituent fibers include 30% by mass or more of hydrophilic fibers.   The nonwoven fabric according to any one of claims 1 to 4, wherein a width of the stripe A is 6 mm to 12 mm.   A wiping material comprising the nonwoven fabric according to any one of claims 1 to 5.

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