Substrate for manufacturing nonwoven fabric

Abstract

To provide a substrate for manufacturing nonwoven fabric, which allows for manufacturing a nonwoven fabric having a horizontal stripe pattern in which at least two types of belt-like parts extending in traverse direction (CD direction) of the nonwoven fabric and having different patterns are repeatedly and regularly disposed in longitudinal direction (MD direction) of the nonwoven fabric.SOLUTION: Fiber web is placed on a substrate for manufacturing nonwoven fabric during manufacturing of a nonwoven fabric. The substrate for manufacturing nonwoven fabric is formed by weaving warp and weft and includes at least two types of a woven texture A and a woven texture B. The woven texture A and the woven texture B are belt-like parts extending along a direction in which the weft extends. The woven texture A and the woven texture B are regularly and repeatedly formed along the direction in which the warp extends on the substrate for manufacturing nonwoven fabric.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a support for use in the production of nonwoven fabrics, on which a fibrous web is placed during the production of nonwoven fabrics, and which allows a pattern to be applied to the fibrous web while the fibers are being integrated. [Background technology]

[0002] A method has already been proposed for producing a nonwoven fabric by appropriately selecting a support for nonwoven fabric production (hereinafter sometimes simply referred to as "support") on which a fibrous web is placed to obtain a nonwoven fabric having a pattern corresponding to the structure of the support. For example, when producing a nonwoven fabric by spraying a high-pressure fluid flow onto a fibrous web to entangle the fibers, it has been proposed to place the fibrous web on a support capable of forming a pattern on the nonwoven fabric and rearrange portions of the fibrous web to form a striped pattern (Patent Document 1). Also, an industrial woven fabric having three predetermined pattern region groups has been proposed as an industrial woven fabric for imparting a textured mark to a paper product (Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-287158 [Patent Document 2] Patent No. 4188209 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a support for nonwoven fabric production that can produce a nonwoven fabric having a horizontal stripe pattern in which at least two different types of stripes extending in the cross direction (CD) of the nonwoven fabric are regularly and repeatedly arranged in the machine direction (MD) of the nonwoven fabric. [Means for solving the problem]

[0005] The present disclosure provides a support for nonwoven fabric production, which is formed by weaving warp and weft yarns and on which a fiber web is placed during the production of a nonwoven fabric, At least two types of weave structure A and weave structure B are included, The weave structure A and the weave structure B are belt-shaped portions extending along the direction in which the weft yarn extends, The weave structure A and the weave structure B are regularly and repeatedly formed along the direction in which the warp yarns extend. A substrate for manufacturing a nonwoven fabric is provided. [Effects of the Invention]

[0006] The support of the present disclosure enables the production of nonwoven fabrics with novel designs, in which areas on which patterns derived from weave structure A and areas on which patterns derived from weave structure B are formed are arranged alternately or regularly in the longitudinal direction of the nonwoven fabric. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a structural diagram of an example of a support according to the present embodiment. [Figure 2] FIG. 2 is a structural diagram of an example of a support according to the present embodiment. [Figure 3] 2 is a photograph showing the surface of a nonwoven fabric produced in Example 1, which corresponds to an example of a nonwoven fabric produced using the support of FIG. 1. [Figure 4] 3 is a photograph showing the surface of a nonwoven fabric produced in Example 2, which corresponds to an example of a nonwoven fabric produced using the support of FIG. 2. [Figure 5] FIG. 2 is a structural diagram of an example of a support according to the present embodiment. [Figure 6] 6 is a photograph showing the surface of a nonwoven fabric produced in Example 3, which corresponds to an example of a nonwoven fabric produced using the support of FIG. 5. [Figure 7] 1 is a photograph showing the surface of the nonwoven fabric produced in Example 4. [Figure 8] 1 is a photograph showing the surface of the nonwoven fabric produced in Example 5. [Figure 9] 1 is a photograph showing the surface of the nonwoven fabric produced in Example 6. [Figure 10]1 is a side cross-sectional photograph showing a method for determining the difference in height between the surface of weave structure A and the surface of weave structure B in an example of the support of this embodiment. [Figure 11] 1 is a side cross-sectional photograph showing a method for determining the difference in height between the surface of weave structure A and the surface of weave structure B in an example of the support of this embodiment. [Figure 12] 1 is a side cross-sectional photograph showing a method for determining the difference in height between the surface of weave structure A and the surface of weave structure B in an example of the support of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the nonwoven fabric disclosed in Patent Document 1, the rows or patterned portions constituting the striped pattern extend in the MD (longitudinal) direction of the nonwoven fabric, and two or more different patterned regions are regularly arranged along the CD (transverse) direction (hereinafter, such striped patterns will be referred to as "vertical stripes" for convenience). Patent Document 1, for example, places a fiber web on a herringbone net, and by regularly varying the water jetting conditions in the CD, vertical stripes are formed to form rows having a pattern corresponding to the substrate. Specifically, Patent Document 1 discloses a method in which some of the orifices in a nozzle jetting water are regularly blocked, and a hydroentanglement process is performed to form rows having a pattern corresponding to the substrate at intervals.

[0009] Patent Document 2 proposes using an industrial woven fabric having two specific types of pattern regions and a pattern region made of a plain weave to form recesses and protrusions in a paper product when viewed from the portions where the two specific types of pattern regions are formed corresponding to the plain weave. That is, Patent Document 2 proposes an industrial woven fabric in which recesses and protrusions are formed over a relatively wide area in the paper product, making it possible for the recesses or protrusions to appear as letters, for example.

[0010] In order to obtain a striped pattern not obtainable with conventional nonwoven fabrics, the present inventors focused on the configuration of the support on which a fiber web is placed when producing nonwoven fabrics using a high-pressure fluid entanglement method, a spunbonding method, or the like, and investigated ways to configure the support to be suitable for forming a striped pattern. As a result, they devised a support having at least two different weaves, with the two different weaves arranged alternately along the direction in which the warp threads of the support extend (generally the direction in which the support moves during nonwoven fabric production). With such a support, nonwoven fabrics with novel designs can be produced even under normal high-pressure fluid entanglement or spunbonding conditions. The configuration of the support for nonwoven fabric production of this embodiment is described below.

[0011] The support of this embodiment is a support formed by weaving warp and weft yarns and includes at least two types of weaves, A and B. Weaves A and B are strips extending in the direction of the weft yarns (generally perpendicular to the direction in which the support moves during nonwoven fabric production, hereinafter also referred to as the "CD direction"). Weaves A and B are regularly repeated along the direction of the warp yarns (generally the direction in which the support moves during nonwoven fabric production, hereinafter also referred to as the "MD direction"). Weaves A and B extend across the entire width of the support in the CD direction, or across the entire width of the nonwoven fabric to be produced in the CD direction. By placing a fiber web on this support and subjecting it to a process to integrate the fibers, or by depositing molten or softened fibers on this support, regions having patterns (including no pattern) determined by each weave are formed.

[0012] In the support, for example, weaves A and B are arranged in the order ABAB... along the direction of warp extension (MD). If the regions formed in the nonwoven fabric by weaves A and B of this support are designated as region 1 and region 2, respectively, then in the nonwoven fabric, two regions are formed in the order 1-region 2-region 1-region 2... along the MD, forming a horizontal stripe pattern (i.e., horizontal stripes) in which region 1 and region 2 extend along the CD direction perpendicular to the MD. Furthermore, weave C can be added and arranged in the order ABCABC... along the MD. Examples of weaves include plain weave, twill weave, satin weave, and herringbone weave. For example, weave A may be a 2 / 2 twill weave, weave B a plain weave, and weave C a 3 / 1 twill weave. Using a support incorporating three or more weaves allows the resulting nonwoven fabric to form a horizontal stripe pattern in multiple regions with different surface properties. The exemplified weave may be an irregular weave, such as a broken twill weave. The irregular weave results in dispersed floating warp yarns passing over weft yarns, resulting in dispersed openings or recesses formed by these floating warp yarns, which can impart a unique design to the nonwoven fabric. Furthermore, a support having an irregular weave tends to improve the dimensional stability of the support, prevent meandering (shifting) during travel, and prevent wrinkles when used to manufacture a nonwoven fabric.

[0013] In the support of this embodiment, the diameters of the weft a constituting weave A and the weft b constituting weave B may be different, and the weft a and the weft b may be adjacent to each other at the boundary between weave A and weave B. In addition, in the support of this embodiment, the surface of weave A may be located, for example, at a position higher than the surface of weave B by 0.1 mm to 3.0 mm, particularly 0.5 mm to 2.5 mm, and more particularly 0.8 mm to 2.0 mm. A support having either or both of these configurations may allow the formation of a narrow third region at the boundary between the first and second regions in the nonwoven fabric.

[0014] The difference in surface height between weave structure A and weave structure B is determined by observing the side or cross-section of the support in the MD direction and measuring the difference between the highest point of weave structure A (usually the point where the warp threads float 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 visible on the cross-section depending on the cut location. In this case, the highest point can be found behind the photographed cross-section, or the support can be cut in several different places and the different cut surfaces can be observed to determine the distance between the highest points of each cross-section. However, if the surface of the weave is photographed obliquely on the back side of the cross-section, the warp and weft threads at the back should be ignored when determining the surface height. Depending on the weave of the support, the highest point may be the weft thread or the warp thread.

[0015] 10 to 12 show methods for determining the difference in height between the surfaces of weave structure A and weave structure B from a side cross section of the support. FIG. 10 corresponds to the support of the weave structure shown in FIG. 1, which will be described later. In FIG. 10, a line LB is drawn that passes through the highest point on the surface of weave structure B and is parallel to the surface of the table on which the support is placed, and a line LA is drawn that passes through the highest point on the surface of weave structure A (the highest point on the surface of the weft yarn, indicated by the symbol a1), and is parallel to the surface of the table on which the support is placed. The distance between LA and LB (the distance in the direction perpendicular to the surface of the table on which the support is placed) corresponds to the difference in height between the surfaces of weave structure A and weave structure B.

[0016] Figure 11 corresponds to the support of the weave shown in Figure 2, which will be described later, and Figure 12 corresponds to the support of the weave shown in Figure 5, which will be described later. As in Figure 10, in these figures, LB is a line that passes through the highest point on the surface of weave B and is parallel to the surface of the table on which the support is placed, and LA is a line that passes through the highest point on the surface of weave A (the surface of the highest warp yarn) and is parallel to the surface of the table on which the support is placed. In Figure 11, the surface of weave B is shown obliquely at the back of the side cross section, but this is ignored when determining LB.

[0017] In a support having the above configuration, a step is formed at the boundary between the two weaves, and / or a gap between the weft yarns is likely to be formed that is wider than in other areas. At this step or gap, the fiber web is subjected to the action of the water flow under conditions different from those of the fiber web in weave structures A and B, and / or is affected by suction during the hydroentanglement treatment. As a result, a third area having a pattern different from both the first and second areas may be formed as a narrow area.

[0018] Furthermore, at the boundary between weave structure A and weave structure B, due to factors such as a change in the diameter of the weft yarn and a change in the weave structure, a portion (called a "knuckle") is formed in which the state of the floating warp yarn differs from the floating warp portions in weave structure A and weave structure B, and it is believed that this knuckle forms an opening in the third region of the resulting nonwoven fabric. Furthermore, at the boundary, the weft yarn may, for example, meander and assume a different state from other portions, which is also thought to be a factor in the formation of the third region and / or determine the pattern in the third region.

[0019] The support of this embodiment may be one in which twill weave portions as weave structure A and plain weave portions as weave structure B are alternately formed along the MD. In such a support, the diameter of weft yarn a may be larger than the diameter of weft yarn b. Examples of such a support will be described below, showing weave structures.

[0020] The twill weave portion of weave structure A may be, for example, a weft twill weave with two or more floating weft yarns and one floating warp yarn. Figure 1 is a weft twill weave diagram of a support on which weave structure A, a 1 / 7 weft twill weave portion, and weave structure B, a plain weave portion, are formed. Figure 2 is a weft twill weave diagram of a support on which weave structure A, a 1 / 3 weft offset twill weave portion, and weave structure B, a plain weave portion, are formed. In the weft structure diagram, the colored portions represent warp yarns floating above the weft yarns. Note that Figures 1 and 2, as well as Figure 5 described below, schematically illustrate the repetition of weave structure A and weave structure B, and the numbers of warp and weft yarns constituting each weave shown in the figures are illustrative. Examples of nonwoven fabrics produced using the supports shown in these figures are shown in Figures 3, 4, and 6. However, the numbers of warp and weft yarns in each region of the supports actually used to produce these nonwoven fabrics may differ from those shown.

[0021] In the support of Figure 1, knuckle a is formed at the boundary between the two weaves by the floating portion of the warp. In Figure 1, knuckle a is formed by the warp floating on wefts a and b. In other parts, the warp floats on one weft, and it can be seen that knuckle a is formed by the floating of the warp in a different state from the other parts. The nonwoven fabric produced using this support has a pattern as shown in Figure 3, with a first region having a diagonal line pattern imparted by a twill weave portion (weave structure A) and a second region formed by a plain weave portion (weave structure B) with openings or recesses arranged in a staggered pattern. Furthermore, as a third region, a stitch-like region with relatively clearly formed openings is regularly formed in the order of first region → third region → second region. This nonwoven fabric corresponds to the nonwoven fabric produced in Example 1 described below, and was produced by a method in which a water stream as a high-pressure fluid stream was sprayed onto a fiber web placed on a support as shown in Figure 1 to entangle the fibers.

[0022] In the nonwoven fabric shown in Figure 3, a third region is formed only at the boundary with the first region on the lower side of the figure, as viewed from one second region. The third region is formed when the water stream is sprayed onto the fiber web while the support is moving, sequentially spraying the water from the fiber web at a lower position (weave structure B) on the support toward the fiber web at a higher position (weave structure A). As the support moves forward, the fiber web extending from lower to higher positions is more likely to firmly receive the water stream and be affected by it, which is thought to facilitate the reflection of knuckles and other irregularities in the nonwoven fabric. On the other hand, at the other irregularity, where the water stream is sprayed from the fiber web at a higher position (weave structure A) to the fiber web at a lower position (weave structure B), some of the water stream "flows down" over the fiber web extending from higher to lower positions and is not firmly received by the fiber web, resulting in a weaker degree of entanglement. As a result, openings and / or depressions are less likely to be formed, and a third region with a distinct pattern is not formed, resulting in a nonwoven fabric like that shown in Figure 3.

[0023] In the support shown in Figure 2, knuckle a is a warp thread floating above a single weft thread. Knuckle a is the area where the warp thread passes over thick weft thread a, but before and after the knuckle a in the direction of travel, the warp thread passes over thin weft thread b. Therefore, the arrangement of weft threads (especially the spacing between weft threads) in the vicinity of knuckle a differs from the arrangement of weft threads in other weaves, and it is thought that knuckle a therefore forms a characteristic opening and / or openings in the third region.

[0024] The nonwoven fabric produced using this support has a pattern as shown in FIG. 4, with a first region in which openings provided by a twill weave (weave structure A) are regularly arranged, and a second region in which openings or recesses are formed by a plain weave (weave structure B) and are arranged in a staggered pattern. Furthermore, as a third region, a stitch-like region in which openings are clearly formed is regularly formed from top to bottom in the figure in the order of first region → third region → second region. This nonwoven fabric corresponds to the nonwoven fabric produced in Example 2 described below, and was produced by a method in which a high-pressure fluid stream of water is sprayed onto a fiber web placed on a support as shown in FIG. 2 to entangle the fibers. In the first region of the nonwoven fabric shown in FIG. 4, relatively clear openings are formed at positions corresponding to the floating warp yarns in weave structure A. This is thought to be because weave structure A is a 1 / 3 weft-break twill weave, and the curvature of the floating warp yarns is stronger in the floating warp yarns than in weave structure A of the support shown in FIG. 1, for example, resulting in a more raised floating warp yarn. Furthermore, in the weave design A of the support in FIG. 2, continuous diagonal lines are not formed by the floating warp yarns, and therefore a diagonal pattern is unlikely to be formed in the first region of the obtained nonwoven fabric.

[0025] The nonwoven fabric shown in Fig. 4 also has a configuration in which the first region → the third region → the second region are repeatedly formed, and when viewed from one second region, the third region is formed only at the boundary with the first region on the lower side of the figure. The reason for forming the third region in this way is thought to be the same as the reason explained with reference to Fig. 3 above.

[0026] In the support of this embodiment, the weave A is not limited to one with one warp float, and may be a twill weave with two or more warp floats. The upper limit of the number of warp floats may be, for example, 16, and particularly 10. In this case, the number of weft floats may be, for example, 2 to 16, and particularly 2 to 10. For example, the support of this embodiment may be formed with a weave A that is a 2 / 2 twill weave and a weave B that is a plain weave, as shown in the weave diagram of Figure 5.

[0027] A twill weave portion, in which the number of floating warp yarns is two or more, forms a characteristic knuckle at the boundary with the plain weave portion. As shown in Figure 5, a knuckle N1, which floats on three or more consecutive weft yarns including the weft yarn a and the weft yarn b, is formed at one boundary of the twill weave portion and the plain weave portion. Because this knuckle N1 is long in the vertical direction, it tends to form a vertically long opening at the boundary between the first and second regions.

[0028] 5, a knuckle N2 is formed at the boundary opposite to the boundary on the side where knuckle N1 is formed, in which a warp yarn floats on two or more continuous weft yarns including weft yarn a and weft yarn b, and a knuckle N3 is formed adjacent to one side of knuckle N2, in which a warp yarn floats on two or more continuous weft yarns. Because knuckles N2 and N3 are formed closely to each other, in the resulting nonwoven fabric, a region where two adjacent openings or two openings are connected to form a single larger opening is formed between the first region and the second region.

[0029] In a weave, as in the support shown in Figure 5, when the number of warp floats (the number of wefts on which successive warp threads lie) and the number of weft floats (the number of warp threads on which successive weft threads lie) are the same, the numbers of warp and weft floats will be the same on both main surfaces. Such a support makes it possible to produce nonwoven fabrics with substantially the same pattern regardless of which main surface the fibrous web is placed on. However, in the twill weave portion, the direction of the diagonal lines formed by the warp threads is mirror image between the two main surfaces, and the direction of the diagonal lines formed in the resulting nonwoven fabric will be opposite.

[0030] An example of a nonwoven fabric produced using the support shown in FIG. 5 is shown in FIG. 6. The nonwoven fabric in FIG. 6 corresponds to the nonwoven fabric produced in Example 3 and was produced by spraying a water stream as a high-pressure fluid onto a fiber web placed on a support as shown in FIG. 5 to entangle the fibers. This nonwoven fabric was produced by performing a hydroentanglement process so that the boundary where the knuckles N1 were formed was sprayed first with the water stream, i.e., with the arrow shown on the right side of the structure diagram in FIG. 5 as the direction of travel. In the nonwoven fabric in FIG. 6, the first region has a diagonal line pattern in which diagonal lines with openings and diagonal lines without openings are alternately arranged. The openings correspond to the areas where the warp yarns float in the twill weave portion in FIG. 5. Since the warp yarns floating above two weft yarns in the twill weave portion are adjacent to each other, relatively clear openings are formed in the nonwoven fabric.

[0031] The nonwoven fabric in Figure 6 has a third region formed corresponding to the boundary including knuckle N1 and a fourth region formed corresponding to the boundary including knuckles N2 and N3. The four regions are formed repeatedly in the order of first region → third region → second region → fourth region. Both the third and fourth regions have patterns different from those of the first and second regions, emphasizing the boundary between the first and second regions. Because knuckle N1 is long and floats above three weft yarns, the opening in the third region is larger than the opening formed in the first region, and the direction of the diagonal lines formed by the opening in the first region appears to be changed in the third region. Because knuckle N2 passes over the weft yarns constituting weave A and the weft yarns constituting weave B at the boundary between weaves A and B, the warp yarns on the weave B side reach a lower position before passing under the weft yarns of weave B. This is thought to be what makes the pattern in the fourth region different from the other regions. Furthermore, at the boundary between weave structures A and B, the spacing between weft threads tends to be wider than that in weave structures A and B, which is also thought to make the patterns in the third and fourth regions different from those in the other regions.

[0032] In the nonwoven fabric of Figure 6, regions with a different pattern from the first and second regions are formed at the boundaries on both the upper and lower sides of the figure when viewed from the second region. At knuckles N2 and N3, the warp yarns float above two weft yarns, and they are relatively large. Therefore, even when water flows sequentially across a fiber web spanning from high to low positions, they are susceptible to the influence of the knuckles, and it is thought that a clearer pattern was formed compared to the support of Figures 1 and 2 (where the number of floating warp yarns is one at the knuckle at the boundary of the weave structure on the rear side in the direction of travel).

[0033] The illustrated support is an example, and weaves A and B may be other than those shown in the drawings. The width in the MD direction of each weave, the diameter of the wefts a and b, and the diameter of the warp are also appropriately selected so as to obtain a desired pattern in the nonwoven fabric.

[0034] In the support, the MD dimensions of the weaves A and B determine the MD dimensions of the first and second regions formed in the resulting nonwoven fabric (i.e., the X-direction dimension when the direction in which the first and second regions are repeatedly formed is defined as the X-direction). In this embodiment, the MD dimension of the weave A may be 2 mm to 200 mm, 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. Similarly, the MD dimension of the weave B may be 2 mm to 200 mm, 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 MD dimension of the weave A may be the same as or different from the MD dimension of the weave B. Furthermore, in one support, there may be a plurality of weave structures A with different dimensions in the MD direction, and / or there may be a plurality of weave structures B with different dimensions in the MD direction.

[0035] The warp and weft yarns constituting the support may be filaments with a diameter of, for example, 0.3 mm to 1.2 mm. The diameter of the weft yarn may be, for example, 0.5 mm to 1.2 mm, particularly 0.9 mm to 1.0 mm, and more particularly 0.65 mm to 0.95 mm. Weft yarns a and b may have different diameters. In this case, the difference in diameter between weft yarns a and b may be, for example, 0.1 mm to 0.8 mm, particularly 0.2 mm to 0.7 mm, and more particularly 0.3 mm to 0.6 mm. The greater the difference in diameter between weft yarns a and b, the clearer the pattern in the third and fourth regions of the resulting nonwoven fabric tends to be. However, if the difference is too large, weave B and the fiber web may not come into contact near the boundary between weaves A and B (large gaps may result), making it difficult to form a clear pattern. The warp threads constituting the support are common to both weaves A and B, and the thickness of the warp threads is the same in both weaves A and B.

[0036] The diameter of the warp and weft threads is the length of the longest line segment connecting any two points on the cross section (a cross section obtained by cutting perpendicularly to the length) of the thread (e.g., filament). The diameter can also be determined in this way for filaments with an elliptical, polygonal, bean-shaped, magatama-shaped, star-shaped, etc. cross section. However, as will be described later, for filaments with a flat cross section (including a rectangle with rounded corners), the dimensions of the short and long sides of the rectangle circumscribing the cross section are used as an index of thickness.

[0037] The warp and weft yarns constituting the support may be monofilaments having a flat cross section, and the rectangle circumscribing the cross section may have 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, "flat shape" refers to a shape with a large dimension in one direction, such as a rectangle (oblong), an oblong, or a rectangle with rounded corners, whose dimensions and shape are difficult to grasp solely from the diameter determined by the above method. When the cross section is a perfect rectangle, the short and long sides of the rectangle will have dimensions within the above ranges. The ratio of the long side to 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.

[0038] In this embodiment, the warp yarns constituting the support preferably have a flat shape. This is because using flat warp yarns makes it easier to improve the MD flexibility and dimensional stability of the support compared to using warp yarns with a circular cross section. Furthermore, using flat warp yarns increases the contact area between the warp yarns and the fiber web, which tends to increase the area of ​​openings formed by the floating warp yarns, including knuckles. Furthermore, the bending resistance of the support tends to be improved, particularly when the warp yarns have a rectangular cross section with rounded corners.

[0039] The warp and weft threads constituting the support may be made of one or more materials selected from polyester, polyamide, polyolefin, polyether ether ketone, polyphenylene sulfide, and the like. The warp and weft yarns may be in a form other than monofilament, such as multifilament or spun yarn. In the case of multifilament or the like, the fineness may be used instead of the diameter as an indicator of the thickness of the yarn, and weft yarns a and b having different finenesses may be used.

[0040] The weave density of the support of this embodiment may be, for example, 6 to 123 threads / inch for the warp yarns, particularly 10 to 80 threads / inch, and more particularly 20 to 40 threads / inch. The weave density of the weft yarns may be, for example, 6 to 123 threads / inch, particularly 8 to 60 threads / inch, and more particularly 10 to 20 threads / inch. The higher the weave density, the more easily the nonwoven fabric can be imparted with a clearer pattern by the portions where the warp yarns, including the knuckles, are raised. However, if the weave density is too high, the smoothness of the portions where the warp yarns, including the knuckles, are raised may increase, which may actually reduce the clarity of the pattern.

[0041] When weave structure A is a twill weave, the shape of the diagonal pattern in the first region of the resulting nonwoven fabric varies depending on the monofilament diameter, warp density, and weft density, as well as the number of warp threads floating above and / or sinking below the weft threads in the twill weave. A twill weave is constructed such that the warp threads floating above the weft threads are either adjacent or not adjacent. When the floating warp threads are connected by a straight line, if a diagonal line extending diagonally can be drawn that includes all the floating warp threads, a first region with a diagonal pattern such as that shown in Figures 3 and 6 is obtained. If such a straight line cannot be drawn, a first region with a pattern in which the openings or recesses are less regularly arranged is obtained, as shown in Figure 4.

[0042] When the weave structure B is a plain weave portion, the size of the openings formed in the second region varies depending on the diameter of the monofilaments that make up the structure, and the opening area tends to increase as the diameter of the monofilaments increases. Furthermore, the spacing between openings, between openings and recesses, or between recesses varies depending on the weft density and warp density of the plain weave portion, and the spacing tends to decrease as the weft density and / or warp density increases.

[0043] In the support, weaves A and B may both be plain weaves. In this case, the two weaves can be made different from each other by varying the diameter of the weft yarns and / or the density of the weft yarns. Alternatively, weaves A and B may both be twill weaves. In this case, the two weaves can be made different from each other by one of the following methods: varying the number of warp threads above the weft yarns, varying the number of warp threads below the weft yarns, varying the diameter of the weft yarns, etc.

[0044] If weave B is a plain weave portion with a fine mesh (for example, 80 mesh or more and 100 mesh or less), a second region without a pattern is formed corresponding to the weave. In this case, weave A may be a weave in which a pattern can be formed, such as a twill weave, or a plain weave portion made of large-diameter filaments.

[0045] The support of this embodiment is manufactured by weaving warp and weft yarns in a conventional manner so that weave structure A and weave structure B are regularly repeated. After weaving, the support is preferably subjected to a heat-setting process in which a heat treatment is performed while applying tension to the support in the MD direction (the direction in which the warp yarns extend) or the CD direction (the direction in which the weft yarns extend). Dimensional stability is imparted by the heat-setting process. The tension is preferably, for example, 1 kg / cm or more and 20 kg / cm or less. The temperature is preferably, for example, 80°C or more and 250°C or less.

[0046] The support of this embodiment is suitable for use in a method in which a high-pressure fluid stream (particularly a water stream) is sprayed onto a fibrous web to rearrange and entangle the fibers, thereby integrating the fibers. Examples of nonwoven fabrics produced by this method are as described above.

[0047] The support of this embodiment is also suitable for use in the production of nonwoven fabrics by the spunbonding method. The spunbonding method is a method of producing a nonwoven fabric by opening and depositing melt-spun fibers on a support to produce a fiber web, and then subjecting the fiber web to a treatment (e.g., embossing) to bond the fibers together. The support of this embodiment is preferably used as a support for use in producing a fiber web by depositing melt-spun fibers. This is because when the melt-spun fibers are deposited on the support, the fibers are in a molten or softened state, and the pattern of the support is easily reflected in the fiber web, and this pattern is maintained in the nonwoven fabric. In the spunbonding method, unlike the high-pressure fluid flow entanglement method, the fibers are not rearranged by external forces during the production of the nonwoven fabric. Therefore, openings are less likely to be formed in the nonwoven fabric produced by the spunbonding method, but the unevenness of the portions of the support where the warp yarns are floating (including knuckles) tends to be more clearly reflected and appear.

[0048] Alternatively, the support of this embodiment may be used when a fibrous web is placed on it and the fibers constituting the fibrous web are bonded to each other by the fibers themselves or by an adhesive.

[0049] The support may be endless, with ends connected in the lateral direction (the direction perpendicular to the direction of travel of the support), or rectangular. When a rectangular support is used, the rectangular support of this embodiment may be laid out on top of another endless support and fixed to the other support, thereby enabling continuous production of a nonwoven fabric. [Example]

[0050] The support of this embodiment and the nonwoven fabric produced using the support will be described with reference to examples.

[0051] Example 1 For the support 1, a woven fabric was produced in which weave structure A was a 1 / 7 twill weave and weave structure B was a plain weave, with weave structure A and weave structure B alternately arranged in the MD. For the support 1, polyester monofilaments with a rounded rectangular cross section and circumscribing the cross section with dimensions of 0.88 mm long x 0.57 mm short were used as warp yarns, polyester monofilaments with a diameter of 0.9 mm were used as weft yarns a, and polyester monofilaments with a diameter of 0.45 mm were used as weft yarns b. In the production of the support 1, after weaving was completed, heat setting was performed at 150°C while applying a tension of 2 kg / cm in the MD. For the support 1, the warp density was 30 threads / inch and the weft density was 25 threads / inch. The MD dimension of the weave structure A was 15 mm, and the MD dimension of the weave structure B was 8 mm. For the support 1, the surface of the weave structure A was located 1.5 mm higher than the surface of the weave structure B.

[0052] The difference in surface height between Weave A and Weave B was determined by photographing the MD cross section of the support using an image analysis processor (KH-3000 manufactured by Hirox Co., Ltd.) and using the method described above.

[0053] Using the support 1, a nonwoven fabric was produced in the following manner. A fiber web was produced by mixing 80% by mass of rayon and 20% by mass of PP / PE using a parallel carding machine. The basis weight of this fiber web was about 40 g / m 2 It was. [First water flow entanglement treatment (total entanglement treatment)] The above-mentioned fiber web was placed on a plain weave net with a warp diameter of 0.132 mm, a weft diameter of 0.132 mm, and a mesh count of 90. While the fiber web was traveling at a speed of 4 m / min, a columnar water stream at a water pressure of 1.0 MPa was sprayed onto the front surface of the fiber web, and then a columnar water stream at a water pressure of 1.5 MPa was sprayed onto the back surface of the fiber web. A nozzle with orifices with a hole diameter of 0.12 mm spaced 0.6 mm apart was used to spray the water stream. The distance between the surface of the fiber web and the orifices was 15 mm.

[0054] [Second water jet entanglement treatment (striped pattern formation treatment)] The fiber web after the first hydroentanglement treatment was placed on a support 1, and while the fiber web was traveling at a speed of 4 m / min, a columnar water stream was sprayed onto the back surface of the fiber web at a water pressure of 1.5 MPa. The same nozzle as that used in the first hydroentanglement treatment was used to spray the water stream. The second hydroentanglement treatment resulted in a nonwoven fabric having first to third regions as shown in Figure 3. More specifically, each region extended along the CD direction (i.e., the CD direction was the Y direction), and a diagonal line pattern portion as the first region and a pattern portion with staggered openings as the second region were alternately repeated in the MD direction to form a striped pattern. The third region was a region consisting of slightly larger openings arranged linearly between the first and second regions.

[0055] [Heat treatment] The nonwoven fabric after the second hydroentanglement treatment was heated at 135°C for approximately 5 seconds using a hot air penetration type heat treatment machine to carry out a drying treatment, and at the same time, the fibers were thermally bonded together by the PP / PE sheath component to obtain the nonwoven fabric of Example 1.

[0056] Example 2 For the substrate 2, a woven fabric was produced in which weave structure A was a 1 / 3 broken twill weave (broken twill + 4 warp threads in 1 weave), weave structure B was a plain weave, and weave structure A and weave structure B were arranged alternately in the MD. For the substrate 2, polyester monofilaments with a rounded rectangular cross section and circumscribing the cross section, measuring 0.88 mm long x 0.57 mm short, were used as warp yarns. Weft yarn A was a polyester monofilament with a diameter of 0.8 mm, and weft yarn B was a polyester monofilament with a diameter of 0.45 mm. After weaving, the substrate 2 was heat-set at 150°C under a tension of 2 kg / cm in the MD. For the substrate 2, the warp density was 30 threads / inch and the weft density was 17 threads / inch. The MD dimension of weave structure A was 15 mm, and the MD dimension of weave structure B was 8 mm. In the support 2, the surface of the weave A was located 1.0 mm higher than the surface of the weave B.

[0057] The nonwoven fabric of Example 2 was obtained in the same manner as in Example 1, except that Support 2 was used in the second hydroentanglement treatment. The second hydroentanglement treatment yielded a nonwoven fabric having first to third regions as shown in Figure 3. More specifically, each region extended along the CD direction (i.e., the CD direction was the Y direction), and a pattern portion in which openings were irregularly formed as the first region and a pattern portion in which openings were arranged in a staggered pattern as the second region were alternately repeated in the MD direction to form a striped pattern. The third region was a region in which slightly larger openings were arranged linearly between the first and second regions.

[0058] Example 3 For the support 3, a woven fabric was produced in which weave structure A was a 2 / 2 twill weave and weave structure B was a plain weave, with weave structure A and weave structure B alternately arranged in the MD. For the support 3, polyester monofilaments with a rounded rectangular cross section and circumscribing the cross section, each having a long side of 0.88 mm and a short side of 0.57 mm, were used as warp yarns. Weft yarn A was a polyester monofilament with a diameter of 0.9 mm, and weft yarn B was a polyester monofilament with a diameter of 0.45 mm. After weaving, the support 3 was heat-set at 150°C while applying a tension of 2 kg / cm in the MD. For the support 3, the warp density was 30 threads / inch, the weft density was 17 threads / inch, the MD dimension of weave structure A was 20 mm, and the MD dimension of weave structure B was 10 mm. For the support 3, the surface of weave structure A was 0.8 mm higher than the surface of weave structure B.

[0059] The nonwoven fabric of Example 3 was obtained in the same manner as in Example 1, except that Support 3 was used in the second hydroentanglement treatment. The second hydroentanglement treatment resulted in a nonwoven fabric having first to fourth regions as shown in Figure 6. More specifically, each region extended along the CD direction (i.e., the CD direction was the Y direction), and a diagonal line pattern portion as the first region and a pattern portion with staggered openings as the second region were alternately repeated in the MD direction to form a striped pattern. A third region and a fourth region were formed at the boundaries between the first and second regions.

[0060] Example 4 For the support 4, a woven fabric was produced in which weave structure A was a 1 / 7 twill weave and weave structure B was a plain weave, with weave structure A and weave structure B arranged alternately in the MD. For the support 4, polyester monofilaments with a rounded rectangular cross section and circumscribing the cross section, with the long side measuring 0.88 mm and the short side measuring 0.57 mm, were used as warp yarns, and polyester monofilaments with a diameter of 0.9 mm were used as weft yarns a and 0.45 mm as weft yarns b. After weaving, the support 4 was heat-set at 150°C while applying a tension of 2 kg / cm in the MD. For the support 4, the warp density was 30 threads / inch and the weft density was 25 threads / inch. The MD dimension of the weave structure A was 15 mm, and the MD dimension of the weave structure B was 20 mm. For the support 4, the surface of the weave structure A was 1.6 mm higher than the surface of the weave structure B.

[0061] The nonwoven fabric of Example 4 was obtained in the same manner as in Example 1, except that a support 4 was used in the second hydroentanglement treatment. The second hydroentanglement treatment yielded a nonwoven fabric having first to third regions as shown in Figure 10. More specifically, each region extended along the CD direction (i.e., the CD direction was the Y direction), and a diagonal line pattern portion as the first region and a pattern portion with staggered openings as the second region were alternately repeated in the MD direction to form a striped pattern. The third region was a region in which slightly larger openings were arranged linearly between the first and second regions.

[0062] Example 5 For the support 5, a woven fabric was produced in which weave structure A was a 2 / 2 twill weave and weave structure B was a plain weave, with weave structure A and weave structure B alternately arranged in the MD. For the support 5, polyester monofilaments having a rectangular cross section with rounded corners and circumscribing the cross section with dimensions of 0.88 mm long x 0.57 mm short were used as warp yarns, polyester monofilaments with a diameter of 0.9 mm were used as weft yarns a, and polyester monofilaments with a diameter of 0.45 mm were used as weft yarns b. In the production of the support 5, after weaving was completed, heat setting was performed at 150°C while applying a tension of 2 kg / cm in the MD. For the support 5, the warp density was 30 threads / inch and the weft density was 17 threads / inch. The MD dimension of the weave structure A was 6 mm, and the MD dimension of the weave structure B was 6 mm. For the support 5, the surface of the weave structure A was located 0.6 mm higher than the surface of the weave structure B.

[0063] The nonwoven fabric of Example 5 was obtained in the same manner as in Example 1, except that a support 5 was used in the second hydroentanglement treatment. The second hydroentanglement treatment yielded a nonwoven fabric having first to fourth regions as shown in Figure 11. More specifically, each region extended along the CD direction (i.e., the CD direction was the Y direction), and a first region, which was a diagonal line pattern, and a second region, which was a pattern with staggered openings, were alternately repeated in the MD direction to form a striped pattern. At the boundary between the first and second regions, third and fourth regions, each consisting of a linear arrangement of slightly larger openings, were formed.

[0064] Example 6 For the support 6, a woven fabric was produced in which weave structure A was a 2 / 2 twill weave and weave structure B was a plain weave, with weave structure A and weave structure B arranged alternately in the MD direction. In the support 6, polyester monofilaments having a rectangular cross section with rounded corners and circumscribing the cross section with dimensions of long sides 0.88 mm x short sides 0.57 mm were arranged alternately as warp threads, and polyester monofilaments with a diameter of 0.9 mm were used as weft threads a and 0.45 mm as weft threads b. In the production of the support 6, after weaving was completed, heat setting was performed at 150°C while applying a tension of 2 kg / cm in the MD direction. In the support 6, the warp density was 30 threads / inch and the weft density was 17 threads / inch. The MD dimension of the weave structure A was 10 mm, and the MD dimension of the weave structure B was 10 mm. In the support 6, the surface of the weave structure A was located 0.45 mm higher than the surface of the weave structure B.

[0065] The nonwoven fabric of Example 6 was obtained in the same manner as in Example 1, except that a support 6 was used in the second hydroentanglement treatment. The second hydroentanglement treatment yielded a nonwoven fabric having first to third regions as shown in Figure 12. More specifically, each region extended along the CD direction (i.e., the CD direction was the Y direction), and a diagonal line pattern portion as the first region and a pattern portion with staggered openings as the second region were alternately repeated in the MD direction to form a striped pattern. At the boundary between the first and second regions, third and fourth regions were formed, each consisting of a linear arrangement of slightly larger openings.

[0066] This embodiment includes the following aspects. (Aspect 1) A support for nonwoven fabric production, on which a fiber web is placed during the production of a nonwoven fabric, comprising warp yarns and weft yarns woven together, At least two types of weave structure A and weave structure B are included, The weave structure A and the weave structure B are belt-shaped portions extending along the direction in which the weft yarn extends, The weave structure A and the weave structure B are regularly and repeatedly formed along the direction in which the warp yarns extend. Support for nonwoven fabric production. (Aspect 2) The support for nonwoven fabric production of aspect 1, wherein the diameters of the weft yarns a constituting the weave structure A and the weft yarns b constituting the weave structure B are different, and the weft yarns a and b are adjacent to each other at the boundary between the weave structure A and the weave structure B. (Aspect 3) A support for producing a nonwoven fabric according to aspect 1 or 2, wherein the surface of the weave A is located at a position higher than the surface of the weave B by 0.1 mm or more and 3.0 mm or less. (Aspect 4) A support for producing a nonwoven fabric according to any one of Aspects 1 to 3, wherein the warp yarns, the weft yarns a, and the weft yarns b are each monofilaments having a diameter of 0.3 mm or more and 1.2 mm or less, or monofilaments having a flat cross section, a rectangle circumscribing the cross section having short sides of 0.2 mm or more and 0.8 mm or less and long sides of 0.3 mm or more and 1.2 mm or less, and a long side / short side ratio of 1.2 or more. (Aspect 5) A support for nonwoven fabric production according to any one of aspects 1 to 4, wherein the weave structure A is a weft twill weave having two or more floats of weft yarns and one float of warp yarns, and the weave structure B is a plain weave structure. (Aspect 6) A support for producing a nonwoven fabric according to any one of aspects 1 to 5, wherein the weft yarns a are thicker than the weft yarns b. (Aspect 7) A support for producing a nonwoven fabric according to any one of aspects 1 to 6, wherein a knuckle N1 where the warp yarn floats is formed on two or more continuous weft yarns including the weft yarn a and the weft yarn b at the boundary between the weave structure A and the weave structure B. (Aspect 8) A support for producing a nonwoven fabric according to any one of embodiments 1 to 7, wherein, as viewed from the weave structure A, at the boundary with the weave structure B on the side opposite to the side where the knuckle N1 is formed, a knuckle N2 is formed in which a warp yarn floats on two or more continuous weft yarns including the weft yarn a and the weft yarn b, and a knuckle N3 is formed adjacent to either side of the knuckle N2 in which a warp yarn floats on two or more continuous weft yarns. (Aspect 9) A support for nonwoven fabric production according to any one of aspects 1 to 8, wherein the weave structure A is a twill weave having 2 or more and 16 or less floats of weft yarns and 2 or more and 16 or less floats of warp yarns, the weave structure B is a plain weave structure, and the diameter of the weft yarn a is larger than the diameter of the weft yarn b. (Aspect 10) A support for producing a nonwoven fabric according to any one of Aspects 1 to 9, which is used in entangling fibers with a high-pressure fluid stream. (Aspect 11) A support for producing a nonwoven fabric according to any one of embodiments 1 to 9, which is used when producing a nonwoven fabric by a spunbond method. (Aspect 12) Producing a fibrous web; The fiber web is placed on a support for producing a nonwoven fabric according to any one of aspects 1 to 10, and the fibers constituting the fiber web are subjected to a treatment for bonding and / or entangling each other. A method for producing a nonwoven fabric, comprising: (Aspect 13) A method for producing a nonwoven fabric, comprising depositing filaments obtained by melt-spinning a synthetic resin onto a support for nonwoven fabric production according to any one of aspects 1 to 9 while the synthetic resin is melted or softened. [Industrial Applicability]

[0067] The support for nonwoven fabric production disclosed herein enables the production of a novel striped nonwoven fabric in which bands of different patterns extending in the CD direction of the nonwoven fabric are regularly arranged in the MD direction, and is useful as a support used in the production of nonwoven fabrics by high-pressure fluid flow entanglement processing and spunbonding methods.

Claims

1. A support for nonwoven fabric production, on which a fiber web is placed during the production of the nonwoven fabric, comprising warp yarns and weft yarns woven together, At least two types of weave structure A and weave structure B are included, The weave structure A and the weave structure B are belt-shaped portions extending along the direction in which the weft yarn extends, The weave structure A and the weave structure B are regularly and repeatedly formed along the direction in which the warp yarns extend. Support for nonwoven fabric production.

2. The support for nonwoven fabric production according to claim 1, wherein the diameters of the weft thread a constituting the weave structure A and the weft thread b constituting the weave structure B are different, and the weft thread a and the weft thread b are adjacent to each other at the boundary between the weave structure A and the weave structure B.

3. 3. The support for producing nonwoven fabrics according to claim 1, wherein the surface of the weave structure A is located at a position higher than the surface of the weave structure B by 0.1 mm to 3.0 mm.

4. 4. A support for nonwoven fabric production according to claim 1, wherein the warp thread, the weft thread a, and the weft thread b are each a monofilament having a diameter of 0.3 mm or more and 1.2 mm or less, or a monofilament having a flat cross section, a rectangle circumscribing the cross section having short sides of 0.2 mm or more and 0.8 mm or less and long sides of 0.3 mm or more and 1.2 mm or less, and a long side / short side ratio of 1.2 or more.

5. The support for nonwoven fabric production according to any one of claims 1 to 4, wherein the weave structure A is a weft twill weave having two or more floating weft yarns and one floating warp yarn, and the weave structure B is a plain weave structure.

6. The support for producing a nonwoven fabric according to claim 1 , wherein the weft threads a are thicker than the weft threads b.

7. 7. The nonwoven fabric manufacturing support according to claim 1, wherein a knuckle N1 is formed at the boundary between the weave structure A and the weave structure B, on two or more continuous weft yarns including the weft yarn a and the weft yarn b, where the warp yarn floats.

8. A support for producing nonwoven fabrics according to any one of claims 1 to 7, wherein, as viewed from the weave structure A, at the boundary with the weave structure B on the side opposite to the side on which the knuckle N1 is formed, a knuckle N2 is formed in which a warp thread floats on two or more continuous weft threads including the weft thread a and the weft thread b, and a knuckle N3 is formed adjacent to either side of the knuckle N2 in which a warp thread floats on two or more continuous weft threads.

9. The support for nonwoven fabric production according to any one of claims 1 to 4 and 6 to 8, wherein the weave structure A is a twill weave having a number of weft floats of 2 to 16 and a number of warp floats of 2 to 16, the weave structure B is a plain weave, and the diameter of the weft thread a is larger than the diameter of the weft thread b.

10. The support for producing a nonwoven fabric according to any one of claims 1 to 9, which is used when entangling fibers with each other by a high-pressure fluid flow.

11. The support for producing a nonwoven fabric according to any one of claims 1 to 9, which is used when producing a nonwoven fabric by a spunbonding method.

12. Producing a fibrous web; The fiber web is placed on the support for producing a nonwoven fabric according to any one of claims 1 to 10, and the fiber web is subjected to a treatment for bonding and / or entangling the fibers constituting the fiber web. A method for producing a nonwoven fabric, comprising:

13. A method for producing a nonwoven fabric, comprising depositing filaments obtained by melt spinning a synthetic resin onto a support for producing a nonwoven fabric according to any one of claims 1 to 9 or claim 11 while the synthetic resin is molten or softened.

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