TWI720163B - Patterned nonwoven fabric and method for manufacuring the same - Google Patents

Abstract

The present invention provides a patterned nonwoven fabric exhibiting a more excellent design effect and having better balance in strength in the longitudinal direction and in the lateral direction.

The patterned nonwoven fabric 100 has a low density region 10, a first high density region 12, and a second high density region 14, wherein a plurality of low density regions are gathered to form one island-shaped portion 20; in one island-shaped portion, the second high-density region 14 is formed at least between the low-density region and the low-density region, and the first high-density region is formed between the island-shaped portion and the island-shaped portion. The fiber density in the first high density region is smaller than the fiber density in the second high density region and the fiber density in the low density region is smaller than the fiber density in the first high density region, or the low density region is the opening part, the total area of the low density region is 0.1% to 12% with respect to the total area of the nonwoven fabric, and the total of the area of the island-shaped portion is 1% to 45% with respect to the total area of the nonwoven fabric.

Description

Non-woven fabric with pattern and manufacturing method of the non-woven fabric

The present invention relates to a patterned non-woven fabric with a pattern formed by arranging a plurality of parts with different fiber densities, and a method of manufacturing the non-woven fabric.

As a patterned nonwoven fabric and a method of manufacturing the nonwoven fabric, various methods have been proposed in the past. For example, the manufacturing method of non-woven fabric disclosed in Patent Document 1 is composed of a plurality of fluid penetrating parts and a supporting member made by continuously expanding the fluid impermeable part around the fluid penetrating part, and a plurality of holes arranged in Between the forming members, the fiber layer is sandwiched. Through the action of the pressure fluid, the penetrating part and the non-penetrating part of the supporting member are arranged corresponding to the high-density part and the low-density part. The high-density part is further formed correspondingly The holes of the component can be rearranged if there are other low-density parts, and the high-density parts will be cross-linked with each other through the substantially row-shaped fibers, so that a non-woven fabric can be manufactured.

Patent Document 2 discloses a non-woven fabric that has a striped pattern by having a plurality of stripes, and the width of the stripes is 4mm to 50mm, and the stripes are made from the constituent fibers of the fiber web intertwined by the constituent fibers A part of it is re-arranged and formed by the entanglement of water, each with regular patterns and stripes separated from each other.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 54-10666

[Patent Document 2] JP 2009-287158 A

The purpose of the present invention is to provide a patterned nonwoven fabric that exerts a different design effect from the conventional patterned nonwoven fabric, and has a better balance of longitudinal and lateral strength, and a method for manufacturing the patterned nonwoven fabric.

One of the main points of the present disclosure is to provide a non-woven fabric with a pattern, which has a low-density area, a first high-density area, and a second high-density area, wherein the aforementioned low-density areas are grouped in plural to form an island shape Section, in the one island-shaped section, the second high-density region is formed at least between the low-density region and the low-density region, and the first high-density region is formed on the island-shaped section and the island. Between the portions, the fiber density of the first high-density area is less than the fiber density of the second high-density area, The fiber density of the low-density region is smaller than the fiber density of the first high-density region, or the low-density region is an open portion, and the total area of the low-density region is From 0.1% to 12%, the total area of the island-shaped portion is 1% to 45% relative to the total area of the non-woven fabric with the pattern.

The patterned non-woven fabric of the present disclosure is a method in which three regions with different fiber densities (low density region, first high density region, and second high density region) try to gather multiple low density regions to form islands. Arrangement, while arranging the second high-density area between low-density areas in the island-shaped portion, and arranging the first high-density area as the base between the island-shaped portions, thereby forming a pattern. Such a trick is to give play to the appearance design effect that has never been seen before. In addition, since the nonwoven fabric of the present disclosure constitutes the pattern part as an island surrounded by the base part, the formation of the pattern improves the strength balance between the vertical and horizontal directions. In addition, in the nonwoven fabric of the present disclosure, the total area of the low-density region is 0.1% to 12% relative to the total area of the nonwoven fabric, and the total area of the island-shaped portion is 1% to 45% relative to the total area of the nonwoven fabric. Play a higher design effect and have good handling properties.

10.10A: low density area

12: The first high-density area

14: The second high-density area

20: Island

20a: circular island with large diameter

20b: Small diameter circular island

20c, 20d: Heart-shaped island

30: Pattern formation support

32: Cotton net

34: Drum (opening member)

36: Opening

38: Nozzle

100: non-woven

a1, a2: spacing

b1, b2: interval

Figure 1 is a plan view schematically showing the nonwoven fabric of this embodiment.

Figure 2 is an enlarged plan view showing the island-shaped portion.

Figure 3 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 4 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 5 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 6 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 7 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 8 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 9 is a photograph showing the surface of an example of the nonwoven fabric of this embodiment.

Figure 10 is a side view showing an example of the arrangement of nozzles, opening members, cotton nets, and pattern formation supports when forming low-density regions and second high-density regions in the production of the nonwoven fabric of this embodiment.

The non-woven fabric of this embodiment is a non-woven fabric with a pattern. It has a low-density area, a first high-density area, and a second high-density area. In each island-shaped portion, a second high-density area is formed at least between the low-density area and the low-density area, The first high-density area is formed between the island-shaped portion and the aforementioned island-shaped portion. The fiber density of the first high-density area is less than that of the second high-density area, and the fiber density of the low-density area is less than that of the first high-density area. The fiber density of the area, or the low-density area is the open hole.

Figure 1 is a plan view schematically showing an example of this nonwoven fabric.

In the non-woven fabric 100 shown in FIG. 1, nine circular low-density regions 10 are gathered to form one island 20, and a first high-density region 12 is formed between the islands 20. The low-density areas 10 are arranged in a chidori shape, that is, in the vertical and horizontal directions, the low-density area 10 of the second row is arranged between two low-density areas 10 in a certain row, forming a regular chidori shape Houndstooth pattern. In a modified example, the low-density regions 10 may be arranged in a square. The low-density regions 10 are independent of each other, and a second high-density region 14 is formed between the low-density regions 10. The entire system of the island portion 20 has a slightly rhombic or circular shape, and is arranged in a chidori shape. In other words, this non-woven fabric 100 is a non-woven fabric with the first high-density region 12 as a base, and islands 20 composed of the low-density region 10 and the second high-density region 14 are regularly formed to form a pattern.

The low-density area 10 is the area with the smallest fiber density among the three areas, and may be a portion having the same thickness as the other areas (that is, it may not be formed with unevenness), a recessed portion, or an open hole portion. The low-density area 10 is as described later. For example, a high-pressure fluid (high-pressure gas such as compressed air, high-pressure liquid such as high-pressure water, etc.) is implemented by arranging a web on a fabric composed of relatively thick monofilaments. ) The entanglement processing, weaving in place The fiber web at the intersection (the highest part) of the object is formed by moving the fibers around by the action of the high-pressure fluid, and then re-arrangement (hereinafter also referred to as “moving”). In the case of forming the low-density region 10 in this way, each area of the low-density region 10 is mainly determined by the thickness of the yarn constituting the fabric. Alternatively, the low-density region 10 may be formed by a formed body or a spiral net having at least one selected from the group consisting of convex parts, concave parts, and openings.

When the low-density area is a recessed portion or an open-hole portion, in the island-shaped portion, the low-density area can be grouped in plural to form a regular pattern. Regular patterns refer to patterns formed by arranging low-density areas according to certain rules. Regular patterns, for example, can be selected from dot pattern, herringbone pattern, checkerboard pattern, lattice pattern, plover pattern, diagonal stripe pattern, wave pattern and zigzag pattern. At least one of the group. When a regular pattern is formed in the low-density area, the design of the non-woven fabric can be improved. In addition, by forming a regular pattern in the low-density area, the air permeability, liquid permeability, liquid retention, and wiping properties of the non-woven fabric can be improved. The regular pattern, as described later, can be formed by arranging a cotton net on a support regularly arranged with at least one selected from the group consisting of protrusions, recesses, and openings, and impacting the high-pressure fluid.

Each low-density area 10, for example, may have ^{an area of 0.03 mm 2} to 20 mm ² , in particular, may have ^{an area of 0.1 mm 2} to 10 mm ² , and more particularly, may have an area of ^{0.7 mm 2} to 5.0 mm ² . The low-density area 10 is too small to fully recognize the low-density area 10, and the appearance design effect may not be fully utilized in some cases. When the low-density region 10 is too large, the non-woven fabric is likely to be deformed or damaged such as elongation, twisting, and cracking, and the handling properties will be reduced. In addition, when the low-density area 10 is too large, sometimes it may be difficult to identify the low-density area, and the effect of the appearance design cannot be fully exerted after all.

The low-density region 10 is at least a region where the fiber density is lower than the first high-density region 12, for example, may have ^{a fiber density of 0 g/cm 3} to 0.080 g/cm ³ , and in particular, may have a fiber density of 0 g/cm ³ to 0.070 g/cm ^{The fiber density of 3} , more particularly, may have a fiber density of 0 g/cm ³ to 0.05 g/cm ³ . The fact that the fiber density is 0 means that the low-density region 10 is an open hole. When the fiber density of the low-density region 10 is large and the difference between the fiber density of the first high-density region 12 is small, the pattern is difficult to recognize, and a sufficient design effect may not be exerted in some cases.

In addition, the total area of the low-density region (that is, the total area of all low-density regions in the non-woven fabric) can account for, for example, 0.1% to 12%, especially 0.5% to 10%, of the total area of the non-woven fabric. 1.0% to 9%, and especially 1.5% to 8%. When the ratio of low-density area (area ratio) is within this range, the increase in strength due to the second high-density area formed between the low-density areas is more advantageous than the decrease in strength caused by the formation of low-density areas , Compared with not forming islands (low-density area and second high-density area), the strength of the non-woven fabric can be effectively improved (especially the stress at 10% elongation). When the total ratio of the area of the low-density region becomes too large, the strength of the non-woven fabric will decrease, and the non-woven fabric is likely to be deformed or damaged such as elongation, twisting, and cracking.

In one island 20 or in one non-woven fabric 100, the fiber density, shape, and area of the low-density regions 10 do not have to be the same. For example, in one island 20, some low-density regions 10 are open-hole sections, and other low-density regions 10 may be non-open-hole sections.

The pitch between the low-density regions 10 is not particularly limited. For example, it may be 0.1 mm to 50 mm in at least one direction, particularly 0.5 mm to 30 mm, and more particularly 1 mm to 10 mm. Here, the pitch is equivalent to the distance between the centers of gravity of adjacent low-density regions 10 in one island-shaped portion 20. In addition, the interval between the low-density regions 10, for example, may be 0.1 mm to 50 mm in at least one direction, particularly may be 0.5 mm to 30 mm, and more particularly may be 1.0 mm to 10 mm. Here, the interval refers to the distance between an arbitrary point on the outer circumference (contour) of the low-density region 10 and the outer circumference (contour) of other low-density regions 10 adjacent to the low-density region 10 in one island 20 The shortest line segment among the line segments connected by any point.

In one island 20 or one non-woven fabric 100, the spacing and interval between the low-density regions 10 may not be constant. For example, as shown in Fig. 2 where the island-shaped portion 20 of the non-woven fabric shown in Fig. 1 is enlarged and shown in Fig. 2, when the low-density area 10 is arranged in a thousand birds shape, the pitch (a1, a2 in the figure) and The interval (b1, b2 in the figure) is a different value depending on the direction, but in this embodiment, it is better to have at least the shortest interval and the shortest interval within the above-mentioned ranges. The intervals and intervals in all directions are Those within the above range are more preferable.

The second high-density area 14 is formed at least between the low-density area 10 and the low-density area 10, and is an area having a higher fiber density than the first high-density area 12. The second high-density region 14 is as described above. When the fibers are moved by the action of the high-pressure fluid to form the low-density region 10, the moved fibers are tightly assembled regions. Because the fibers move around the low-density region 10, for example, in the first figure, the outside of the low-density region 10A located outside (for example, in the part surrounded by a dotted line in the figure) is generally formed with a second high-density region 14. However, there are cases where the boundary between the second high-density region 14 and the first high-density region 12 is not clear. The dotted lines shown in Fig. 1 and other drawings are used to express the concept of the island portion 20 and do not clearly indicate the range of the second high-density region 14. Please pay attention to this point.

The second high-density area 14 has a higher fiber density than the first high-density area 12. For example, it may have a fiber density of 0.01 g/cm ³ to 0.30 g/cm ³ , and in particular, it may have a fiber density of 0.03 g/cm. ^{A fiber density of 3} to 0.20 g/cm ³ , and more particularly, a fiber density of 0.05 g/cm ³ to 0.15 g/cm ³ may be used. In addition, the second high-density region 14 may have a thickness of, for example, 0.05 mm to 5.0 mm, in particular, 0.10 mm to 3.0 mm, and more specifically, a thickness of 0.2 mm to 2.0 mm. The second high-density region 14 is formed by a collection of moved fibers when the low-density region 10 is formed. In this region, the fibers are densely assembled with each other, and their thickness is generally greater than that of the first high-density region 12. The thickness is large, and the fiber density becomes high. Here, the fiber density is obtained from the thickness and the weight per unit area of the non-woven fabric measured in a state where the load of the non-woven fabric is not applied. The thickness in the state where no load is applied to the non-woven fabric can be obtained by observing, for example, electron micrographs.

The island-shaped portion 20 is a part of the low-density regions 10 formed by a plurality of groups, and is a part where the second high-density region 12 is formed at least between the low-density regions 10. In the case where the low-density region 10 is an open-hole portion, the island-shaped portion 20 particularly partially exhibits a mesh-like appearance.

The island 20 can be formed by, for example, preparing an opening corresponding to the island 20 and a member that does not penetrate high-pressure fluid between the openings, that is, an opening member (such as a metal plate). The cotton net on the support of the low-density area 10 is formed by the action of the high-pressure fluid passing through the opening. That is, by making the area of action of the high-pressure fluid only the portion corresponding to the island portion 20, an independent island portion 20 having the low-density area 10 and the second high-density area 14 can be formed. Therefore, the area and shape of the island portion 20 are determined in accordance with the area and shape of the opening. However, the area and shape of the island portion 20 are not completely the same as the area and shape of the opening. The reason can be exemplified. The island 20 is formed by the action of the high-pressure fluid passing through the opening, and the actual area of the high-pressure fluid will vary depending on the expansion of the high-pressure fluid and the number of nozzles overlapping the opening. In addition, the pressure of the high-pressure fluid, the diameter of the nozzle, the fineness, stiffness and length of the fiber (these will affect the degree of movement of the fiber), and the weight per unit area and density of the cotton web will also affect the island 20. The area and shape of the This is also the reason why the area and shape of the island portion 20 cannot be the same as the area and shape of the opening.

The island 20 is used in the use of high-pressure fluid (especially high When it is formed by the entanglement treatment of pressurized water, it is a position that is more susceptible to the action of the high-pressure fluid than the first high-density region 12, so the fibers will be tightly entangled and have a higher density than the first high-density region 12 The fiber density. In addition, the island portion 20 is the same as described above. When the low-density region 10 is formed, a region where the fiber moves are also formed. Therefore, at least between the low-density regions 10, the fiber density becomes higher and the second high density Area 14.

The shape of the island portion 20 is not particularly limited, and it can be formed into a circle, an ellipse, a cloud shape, a polygon having three or more sides (including regular polygons), a star shape, a flower, a clover shape, and a heart shape. Any shape formed by straight or curved lines, such as marks or characters. Polygons having three or more sides are, for example, triangles, rhombuses, trapezoids, parallelograms, rectangles (including squares), regular pentagons, and the like. The islands 20 of different shapes and/or sizes can be formed in a single nonwoven fabric.

In a non-woven fabric, the island-shaped portions 20 may be regularly arranged in the same size, for example, may be arranged in a chidori arrangement or a square arrangement. Alternatively, the island-shaped portion 20 may gather a plurality of island-shaped portions of different shapes and/or areas to form a pattern (theme), and the pattern may be arranged in a thousand birds arrangement or a square arrangement. For example, in the non-woven fabric shown in FIGS. 3 to 5, the island-shaped portions 20 of the same size and shape are arranged in a chidori arrangement or a square arrangement. In the nonwoven fabric shown in FIG. 6, the substantially rectangular island-shaped portions 20 are arranged such that rows formed at an angle in the longitudinal direction and arranged at equal intervals and adjacent rows in the lateral direction are in a mirror image relationship with each other.

In the non-woven fabric shown in Figure 7, in a large-diameter circle Around the island-shaped portion 20a, eight small-diameter circular island-shaped portions 20b are arranged to form a pattern, and this pattern is arranged in a thousand birds shape. In the non-woven fabric shown in Figure 8, two heart-shaped islands 20 c and 20 d, one large and one small, form a pattern, which is arranged in a square arrangement. In the nonwoven fabric shown in Fig. 9, island-shaped portions 20 of the same size and shape are arranged at equal intervals in the diagonal direction (two directions) to form a diamond pattern.

All the configurations of the island-shaped parts shown in the figures are illustrative examples, and the configuration of the island-shaped parts is not limited to these. For example, the island-shaped parts may be arranged irregularly, and a collection of a plurality of island-shaped parts may form a pattern (for example, flowers, animals, symbols, characters, etc.).

The size of each island 20 is not particularly limited. For example, its area may be 1.0 mm ² to 18000 ^{mm 2} , particularly 3.0 mm ² to 5000 mm ² , and more particularly 5.0 mm ² to 2000 mm ² . The larger the area of the island-shaped portion 20, the greater the number of low-density regions 10 contained in the island-shaped portion 20. If the area of the island 20 is too small, the opening provided in the opening member will also become smaller, so that high-pressure fluid with sufficient energy cannot pass through the opening, and the formation of the low-density region 10 and the second high-density region 14 may become insufficient The situation. When the area of the island-shaped portion 20 is too large, the pattern formed by the island-shaped portion 20 and the assembly of the island-shaped portion 20 cannot be fully recognized, and the design effect may not be obtained. In particular, when the non-woven fabric is cut and used depending on the purpose, the number of islands 20 or aggregates of islands 20 contained in the cut area decreases due to the size of the cut. , And the pattern formed by the island portion 20 cannot be fully recognized. When the boundary of the island-shaped portion 20 is not clear, the area of the island-shaped portion 20 is a circle that can include all the low-density regions in the island-shaped portion 20, and the diameter can be approximated by the area of the smallest circle.

The distance between the islands 20 is not particularly limited. For example, it may be 5 mm to 100 mm in at least one direction, particularly 7 mm to 80 mm, and more particularly 10 mm to 50 mm. Here, the pitch is equivalent to the distance between the centers of gravity of adjacent island-shaped portions 20.

In addition, the interval between the island-shaped portions 20 may be, for example, 1 mm to 100 mm in at least one direction, specifically, 2 mm to 80 mm, and more specifically, 5 mm to 50 mm. Here, the interval refers to the shortest line segment that connects any point on the outer circumference (contour) of the island-shaped portion 20 with any point on the outer circumference (contour) of the other adjacent island-like portions 20 in the island-shaped portion 20.的线段。 The line segment. The pitch and interval of the islands 20 are the same as the pitch and interval of the low-density region 10, and will have different values depending on the difference in direction. In this case, it is preferable that at least the shortest pitch and interval are within the above-mentioned ranges. It is more preferable that the interval in all directions and the interval are within the above range. When the respective patterns of the island-shaped portions 20 are displayed, if the pitch and interval of 20 are too small, the boundary with the adjacent island-shaped portions may become unclear, and it may be difficult to recognize the pattern shown in the island-shaped portions 20.

Or, the total area of the island-shaped portion 20 (ie, the total area of the island-shaped portions in the non-woven fabric) may account for, for example, 1% to 45%, particularly 3% to 40%, of the total area of the non-woven fabric. Especially 5% to 35%, and especially 7% to 30%. If the ratio (area ratio) occupied by the islands 20 is too small, the desired appearance design effect will not be obtained, and if it is too large, it will be the same as when the area of each island 20 is too large. It is not possible to fully recognize the pattern formed by the island-shaped portion 20 and the assembly of the island-shaped portion 20. In addition, when the ratio of the total area of the island-shaped portions 20 occupied by the non-woven fabric is too large, the interval between the island-shaped portions 20 becomes small, and the pattern shown in the island-shaped portions 20 may not be fully recognized.

In addition, in the above description, the island-shaped portion 20 forms an independent area in the non-woven fabric. Whether or not "islands form an independent area" is judged by the following method.

i) Designate an island (referred to as "island A" for convenience), and an island (referred to as "Island B").

ii) Among the low-density areas contained in the island-shaped portion A, the one closest to the low-density area contained in the island-shaped portion B is regarded as the low-density area A, and among the low-density areas contained in the island portion B , The one closest to the low-density area contained in the island portion A is regarded as the low-density area B.

iii) Measure the distance between the low-density area A and the low-density area B. If the interval between the low-density area A and the low-density area B is greater than the interval between the low-density area contained in the island-shaped portion A and the interval between the low-density area contained in the island-shaped portion B, which is the largest, the island-shaped portion can be said to be Formed independently.

If the distance between the low-density area A and the low-density area B is preferably at least twice the largest of the interval between the low-density area contained in the island-shaped portion A and the interval between the low-density area contained in the island-shaped portion B, and more It is preferably 3 times or more, and more preferably 5 times or more.

The first high-density region 12 is a part that may also be referred to as a base of the non-woven fabric, and is a part located between the island-shaped portion 20 and the island-shaped portion 20. The first high-density area 12 is a high-pressure fluid that has the energy required for the formation of the low-density area and the second high-density area when the high-pressure fluid is applied to the entanglement process using the member having the above-mentioned opening. The part that is not impacted. The first high-density region 12 is a region that has been integrated before the entanglement treatment performed by the high-pressure fluid using a member having an opening, for example, the fibers are mutually integrated by the entanglement treatment performed by the high-pressure fluid. The part where the fibers are entangled in advance, the part where the fibers are intertwined with each other, or the part where the fibers are entangled and connected to each other.

The fiber density of the first high-density region 12 is not particularly limited as long as it is greater than the fiber density of the low-density region 10 and less than the fiber density of the second high-density region 14. For example, it may have 0.01 g/cm ³ to 0.20 g / cm ³ fiber density, 0.03 g of which may have special / cm to 0.15 g of ³ / cm ³ fiber density, and more particularly may have 0.05 g of / cm to 0.13 g of ³ / cm ³ fiber density. Since the first high-density region 12 is used to form the base portion of the island 20 (the low-density region 10, the second high-density region 14), it is difficult to form the fiber density whether it is too small or too large. Good condition of island 20.

The first high-density area, for example, may have a thickness of 0.05 mm to 3.0 mm, particularly may have a thickness of 0.1 mm to 2.5 mm, and more particularly may have a thickness of 0.2 mm to 1.8 mm.

When the low-density area 10 is an open portion, the fiber density of the first high-density area 12 and the second high-density area 14 may have a ratio of 1/1.03 or less (first/second), and may have a ratio of 1/1.05 The ratio of the following (1st / 2nd). In the case of the non-opening part of the low density area 10, low density The fiber density ratio of the region 10 and the first high-density region 12 can be, for example, 1/1.03 or less (low density/first), and in particular, it can be 1/1.05 or less (low density/first). When the density difference between the low-density area 10 and the first high-density area 12, and/or the density difference between the first high-density area 12 and the second high-density area 14 is small, the island 20 is formed The pattern will become unclear, and the design effect will not be fully utilized.

In the nonwoven fabric of this embodiment, the fibers are preferably entangled with each other. That is, in the low-density region (except for the case where it is formed as an open hole), it is preferable that the fibers are entangled in any one of the first high-density region and the second high-density region. The entanglement of fibers makes it easy to clearly and simply form the low-density region, the first high-density region, and the second high-density region. The fibers are preferably entangled by the action of a high-pressure fluid, and more preferably are entangled by the action of a high-pressure liquid (especially high-pressure water). The non-woven fabric in which the fibers are entangled by high-pressure liquid is very good in touch. In addition, the entanglement treatment performed by the high-pressure liquid is easy to remove the excess fiber treatment agent adhering to the fibers. Therefore, the non-woven fabric in which the fibers are entangled with each other by the high-pressure liquid is suitable for undesired adhesion of the fibers. In the application where the treatment agent is attached.

The fibers constituting the non-woven fabric of this embodiment are not particularly limited, and are selected in accordance with the use of the non-woven fabric and the like. The nonwoven fabric of this embodiment can be formed of, for example, one or more fibers selected from the following fibers: Polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, and copolymers thereof, nylon 6, nylon 66, and their copolymers Polyamide resins such as polymers, polymethyl Polyolefin resins such as pentene, polypropylene, polyethylene (including high-density polyethylene, low-density polyethylene, and linear low-density polyethylene), and one or more selected from acrylic resins Synthetic fibers composed of thermoplastic resin; natural fibers such as cotton, silk, wool, hemp, and wood pulp; rayon (rayon) and polynosic (polynosic) obtained by the viscose method, using the cupra method Regeneration of available cupro, cellulose fibers obtained by solvent spinning (Lenzing Lyocell (registered trademark) and Tencel (registered trademark), etc.), and cellulose fibers obtained by melt spinning Fibers (including those whose surface has been treated with a hydrophobizing agent); and, semi-synthetic fibers such as acetate fibers.

Synthetic fibers may be either single fibers or composite fibers. The composite fiber may be, for example, a concentric or eccentric core-sheath composite fiber, a sea-island composite fiber, a side by side composite fiber, or a split composite fiber.

In addition, the synthetic fiber may be melted or softened by heating or the like to exhibit adhesiveness. For example, the synthetic fiber may be a single fiber or a composite fiber containing a relatively low melting point resin such as polyethylene as a component, and the low melting point resin component occupies at least a part of the fiber surface. Such fibers are, for example, core-sheath composite fibers composed of a combination of polyethylene/polypropylene and polyethylene/polyethylene terephthalate, and using polyethylene as the sheath component. When using synthetic fibers that allow fibers to indirectly contact each other, the synthetic fibers may contain, for example, 5 mass% or more in the non-woven fabric, particularly 10 mass% or more, and more particularly 20 mass% or more. on. When the ratio of the adhesive synthetic fiber is too small, the effect of making the fibers indirect with each other may not be sufficiently obtained (described later).

Or, the synthetic fiber may be a latent crimping fiber that exhibits three-dimensional crimping by heating or the like, or an apparent crimping fiber that exhibits three-dimensional crimping when the fiber is manufactured.

The fineness of the fiber is not particularly limited as long as it forms a desired pattern, and it is selected according to the use of the non-woven fabric and the like. The fineness of the fiber may be in the range of 0.1 dtex to 6.6 dtex, and may be in the range of 0.25 dtex to 3.3 dtex, for example.

The fiber length of the fiber is not particularly limited as long as it forms a desired pattern, and it is selected in accordance with the manufacturing conditions of the non-woven fabric. The fiber length of the fiber is, for example, 10 mm or more and 100 mm or less. When the fiber length is outside this range, it becomes difficult to make a fiber web using, for example, a card machine. In addition, in a nonwoven fabric with a low weight per unit area, when the fiber length exceeds 100 mm, the number of fibers constituting the nonwoven fabric is reduced, so the texture of the nonwoven fabric is unstable, or the required strength of the nonwoven fabric cannot be obtained. The fiber length is more preferably 25 mm or more and 100 mm or less, more preferably 32 mm or more and 70 mm or less, and particularly preferably 38 mm or more and 65 mm or less.

The nonwoven fabric of the present embodiment contains cellulose fibers, for example, 20% by mass or more, particularly 40% by mass or more, and more particularly 60% by mass or more. Here, examples of cellulose fibers include natural fibers derived from plants such as cotton, flax, ramie, jute, hemp, and pulp; artificial fibers obtained by the viscose method. Silk and multiple Brain fibers, cupro obtained by the cupro method, cellulose fibers obtained by the solvent spinning method (Lenzing Lyocell (registered trademark) and Tencel (registered trademark), etc.), and fibers obtained by the melt spinning method Regenerated fibers such as plain fibers, and semi-synthetic fibers such as acetate fibers. Cellulosic fibers, especially in the case of non-woven fabrics produced by entanglement treatment using high-pressure water flow, are applied to non-woven fabrics that are easy to entangle each other and remain entangled after the entanglement treatment, so it can be more clear In each area of the region, the non-woven fabric forms a distinctive pattern.

The fibers contained in the non-woven fabric may be synthetic fibers. Or, the non-woven fabric may be composed of a combination of two or more types of fibers. For example, cellulose fibers that have been hydrophobized and cellulose fibers that have not been hydrophobized can be combined to form the nonwoven fabric of this embodiment. In the case of combining synthetic fibers, for example, the synthetic fibers are made of a combination of polyethylene/polyethylene terephthalate, polyethylene/polypropylene, low melting point polyester/polyethylene terephthalate, etc. The core-sheath type composite fiber of the core can be obtained by heat treatment or the like to obtain a non-woven fabric in which the fiber and the fiber are bonded to each other. Such a non-woven fabric has greater strength and higher dimensional stability compared with fibers that are not connected to each other.

The weight per unit area of the nonwoven fabric is not particularly limited as long as it forms a desired pattern, and it is selected due to applications and the like. In order to obtain a non-woven fabric with a fiber density and thickness within the above range in each region, the weight per unit area of the non-woven fabric can be, for example, 10 g/m ² to 300 g/m ² , especially 15 g/m ² to 200 g/m ² , and more In particular, it can be 20 g/m ² to 100 g/m ² , and more particularly, it can be 25 g/m ² to 8 g/m ² . If the weight per unit area of the non-woven fabric is too small, it will be difficult to form three regions with different fiber densities, and if it is too large, it will be particularly difficult to form low-density regions.

When non-woven fabric is used as the surface material of absorbent articles such as napkins and sanitary pads, the weight per unit area of the non-woven fabric can be, for example, 12 g/m ² to 60 g/m ² , especially 18 g/m 2 m ² to 50g/m ² . In addition, when used as a face mask, the weight per unit area of the non-woven fabric can be made 30g/m ² to 250g/m ² , especially 40g/m ² to 120g/m ² , which is used as a human wipe In the case, the weight per unit area of the non-woven fabric can be 10g/m ² to 200g/m ² , especially 15g/m ² to 150g/m ² , as the wiping paper for objects, the weight per unit area of the non-woven fabric , It can be 10g/m ² to 200g/m ² , especially 15g/m ² to 150g/m ² . The examples of the range of weight per unit area suitable for each application described here refer to the weight per unit area of the nonwoven fabric of this embodiment and other nonwoven fabrics when used in a state where the nonwoven fabric of this embodiment is laminated with other nonwoven fabrics. The total weight per unit area of the non-woven fabric after the total weight per unit area.

The non-woven fabric can also be a single-layer structure or a multilayer structure.

In addition, the non-woven fabric may be made of carded webs, air-laid webs, etc. selected from parallel cotton webs, cross-shaped cotton webs, semirandom-laid webs, and random cotton webs. ), wet papermaking webs, and spunbonded webs, etc. formed by cotton webs. Use cellulose fibers as constituents In the case of fibers, the fiber webs that can be formed by using cellulose fibers are carded webs, air-laid webs, and wet papermaking webs, and contain cellulose fibers. The fiber webs suitable for these are clearly formed with patterns. Manufacture of non-woven fabrics.

Next, the manufacturing method of the nonwoven fabric of this embodiment is demonstrated. The non-woven fabric of this embodiment is prepared by first preparing a cotton web selected from the above-listed cotton webs. The entire surface of the non-woven fabric can be entangled with a high-pressure fluid to form the first high-density area, and then partially implemented. It is manufactured by a method of forming islands by the entanglement treatment of high-pressure fluid. The entanglement process performed by high-pressure fluid to form islands can be implemented by the following method: disposing the fiber web on at least one selected from the group consisting of protrusions, recesses, and openings for forming low-density regions On the support (hereinafter, also referred to as "pattern-forming support"), a member (hereinafter, referred to as "opening member") that has an opening and that does not penetrate high-pressure fluid other than the opening (hereinafter referred to as "opening member") is arranged on the jetting high-pressure fluid A method of spraying high-pressure fluid through the opening between the nozzle and the cotton net.

The high-pressure fluid is sprayed through the opening member, thereby allowing only the high-pressure fluid with the energy required to form the low-density area to act on the portion of the cotton web corresponding to the opening, where the fibers are further entangled to increase the density. In addition, the high-pressure fluid sprayed through the opening member acts on the cotton net placed on the pattern-forming support, thereby forming a low-density area corresponding to the shape of the pattern-forming support. When the density zone is formed, the fibers move around to form a second high density zone.

As a high-pressure fluid, compressed air and the like can be cited High-pressure gas and high-pressure liquid such as high-pressure water. It is preferable to use a high-pressure liquid from the viewpoint of obtaining a nonwoven fabric with excellent tactility and the ability to remove excess oil adhering to the fibers. In the manufacture of non-woven fabrics, water flow entanglement treatment using high-pressure water as a high-pressure fluid is often used. In the present embodiment, from the viewpoint of ease of implementation, etc., it is desirable to use water flow entanglement treatment. In the following, a manufacturing method in the case of using high-pressure water (hereinafter, simply referred to as "water flow") as the high-pressure fluid will be described.

First, the formation of the first high-density area that becomes the base is carried out by loading a cotton net on the support and spraying water. The water flow may be a columnar water flow. The first high-density region is preferably formed to have a less dense and uniform texture. Therefore, when forming the first high-density area, it is better to use a support with a finer mesh, for example, a support with a plain weave of 80 mesh to 100 mesh. Water flow entanglement treatment can be achieved by spraying water pressures of 1 MPa to 15 MPa on the surface and inner surface of the cotton net from nozzles with a diameter of 0.05 mm to 0.5 mm at intervals of 0.3 mm to 1.5 mm. Implemented 1 to 5 times. The water pressure is ideally between 1 MPa and 10 MPa, and more preferably between 1 MPa and 7 MPa. The distance between the nozzle and the cotton net can be set to, for example, 5 mm to 100 mm, especially 10 mm to 50 mm.

Next, islands (a low-density area and a second high-density area) are formed. The operation when forming the islands is as described above. The cotton net (hereinafter, also referred to as "primary processing cotton") after the formation of the first high-density area is arranged on the pattern forming support, and, The opening member is arranged between the nozzle and the cotton net.

The pattern forming support may have convex parts. In this case, when the fibers on the convex parts are impacted by the water flow, the fibers can move around to rearrange the fibers to form a low-density area at the position corresponding to the convex parts. . Alternatively, the patterned support may have recesses. In this case, the fibers at the periphery of the recesses can be moved to the recesses and rearranged in the recesses to form a second high-density area at the position corresponding to the recesses. A low-density area is formed around the recess. With the shape of the recesses, the second high-density area can be three-dimensional. Or, the pattern-forming support may have openings. In this case, the fibers around the openings move, move to the openings and rearrange them in the openings, forming a second high-density area at the position corresponding to the openings , A low-density area is formed around the opening. Depending on the shape of the opening, etc., the second high-density area can be three-dimensional. The pattern-forming support may have two or more selected from the group consisting of convex parts, concave parts, and openings.

The pattern forming support can be a fabric made of natural resin, synthetic resin, or metal, a plate-shaped member subjected to punching processing, or a spiral net. In addition, the pattern forming support may be one or more selected from the group consisting of convex parts, concave parts, and openings, which are regularly arranged to have a regular pattern. When such a pattern is used to form the support, in the island-shaped portion, the low-density area can be grouped in plural to form a regular pattern. Regular patterns, such as dot patterns (circles, ellipse circles, triangles, polygons, etc.), herringbone patterns, checkerboard patterns, lattice patterns, thousands of birds pattern, diagonal stripes pattern, spiral net pattern, or It is a zigzag pattern.

Specifically, the pattern-forming support may be, for example, a monofilament with a fiber diameter of about 0.1 mm to 1.2 mm with a warp density of 10 threads per inch. Inches to 30 strands/inch, weft density 10 strands/inch to 30 strands/inch woven into plain weave, twill, and satin fabrics. The support composed of a relatively thick fabric can form a low-density area at the intersection of the weft yarn and the warp yarn as a convex portion. In the case of using such a fabric, each area of the low-density area is determined according to the thickness of the yarns constituting the fabric, and the interval and spacing of the low-density area is determined according to the density of the warp/weft yarns of the fabric.

Alternatively, the pattern-forming support may also have protrusions and/or recesses, such as conical trapezoidal, conical, quadrangular pyramid trapezoidal, or quadrangular pyramidal protrusions, or cutting processing on the surface of the metal plate. The formed concave portion, and the convex portion and/or the portion other than the concave portion, for example, a plate-shaped member (for example, a metal plate) formed by forming a small-sized opening to ensure water permeability.

Alternatively, the pattern-forming support may be a spiral net.

The opening member is a member that is provided with an opening corresponding to the island-shaped portion and does not penetrate high-pressure fluid other than the opening. For example, it may be a metal plate that forms the opening by pressing. In the case of using a high-pressure water stream as a high-pressure fluid, a small hole for draining water can be provided in a part other than the opening. Or, when high-pressure gas is used as the high-pressure fluid, small holes may be provided in parts other than the opening for the purpose of reducing heat generation and pressure loss. The small holes provided outside these openings will not substantially pass the high-pressure fluid, or even after it can pass, the low-density area and the second high-density area will not be formed by the high-pressure fluid passing through. , The water flow through the hole does not have to form a low density Area, etc.), and are formed in a very small size.

The opening member may be a belt shape, or may be a cylindrical drum. In the case of using a cylindrical rotating drum, nozzles can be arranged in the rotating drum to form an island by rotating the rotating drum while spraying water. In the case of using a cylindrical drum, compared with the case of using a belt-shaped opening member, the equipment required to form the second high-density area can be made relatively simple, and the equipment required can be reduced. Accounted for the base. In addition, in the case of using a rotating drum, the rotating drum rotates with its center as the axis of rotation, and does not slide on other members, so the opening will not be worn or deformed during rotation, and it can be used relatively quickly The speed of rotation. In addition, the opening member of the drum is formed by processing a metal plate with a certain thickness to form the opening, so even if it is used for a long period of time, it is not easy to cause deterioration over the years (abrasion and deformation of the opening). During the period, the non-woven fabric of the predetermined pattern will be manufactured stably.

When a cylindrical drum is used and nozzles are arranged in the drum, the water flow can be impacted on the cotton net in the area corresponding to the opening of the drum, and the energy weakening of the water flow and the disorder of the water flow direction can be suppressed. Regarding this, in the case of using a rotating drum, when the side of the pattern-forming support impacts the water flow on the cotton net, the water flow is blocked by the support, which causes the weakening of the water flow energy to increase, and it is necessary to increase the need for interlacing Of water flow energy.

In the case of using a belt-shaped opening member, it is necessary to have equipment and space for continuously moving the long plate-shaped member. In addition, in a belt-shaped opening member, belt abrasion and deformation are likely to occur as the belt is transported, and deformation of the opening is likely to occur along with these. Also, because the belt is It is made using the material of Huiwan music, so it is easy to deform the opening when it is used for a long period of time. Since the opening portion determines the shape of the island-shaped portion, when the opening portion is deformed, the target pattern cannot be obtained in the non-woven fabric.

The shape and area of the opening provided in the opening member are determined in accordance with the shape and area of the island to be formed. Or when the shape and area of the opening of the opening member are determined in advance, the shape and area of the island-shaped portion to be formed are determined according to the shape and area of the opening. For example, each area of the opening, for example, a 3mm ² to 18000mm ^2, is particularly 5mm ² to 2000mm ^2, more particularly can be 19mm ² to 710mm ^2. In addition, the total area of the opening may be 1% to 45% relative to the total area of the opening member, particularly, 3% to 40%, more particularly, 5% to 35%, and even more special It can be 7% to 30%. When the total ratio of each area of the opening and/or the area of the opening is too large, the strength of the opening member will decrease, the opening will be deformed, and the target pattern cannot be obtained in the nonwoven fabric. The example of the shape of the opening is the same as the description of the island-shaped part.

The opening member may be arranged in such a way that the opening member does not contact the primary processing web, that is, it can be arranged in such a way that there is a space between the opening member and the primary processing web. When a water stream is sprayed in a state where the opening member is in contact with the primary processing cotton web, the energy generated by the water flow presses the opening member to the primary processing cotton web. As a result, the surface shape (pattern, etc.) of the opening member itself may be imparted to the non-woven fabric, or the resulting non-woven fabric may be compressed. These effects are in the manufacturing method of this embodiment Middle is not the expected effect.

The opening member, for example, can be configured such that the distance between the opening member and the primary processed cotton net is 0.5 cm to 5.0 cm. The distance between the opening member and the once-processed cotton web can be particularly set to be 1.0 cm to 3.0 cm, and more particularly can be set to be 1.5 cm to 2.5 cm. The distance between the nozzle and the primary processed cotton web is within the range described later. The distance between the opening member and the primary processed cotton web is short. When the two are close, the opening member may accidentally contact the primary processed cotton web. In this case, damage, wrinkles, and fluff will occur in the one-time processing of the cotton web. Also, when the two are close together, the fiber treatment agent (oil agent) adhering to the fibers constituting the cotton web will adhere to the opening member, and the adhesion amount of the fiber treatment agent in the cotton web is less than the predetermined amount, resulting in unsuitability. . The adhesion of the fiber treatment agent to the opening member may require washing of the opening member, or it may accelerate the deterioration of the opening member. Or, the distance between the nozzle and the primary processed cotton web is within the range described later, and when the distance between the opening member and the primary processed cotton web is short, the distance between the nozzle and the opening will become longer, and the nozzle will spray The water flow expands before passing through the opening, and a part of it is shielded by the part outside the opening (the part that does not penetrate the liquid), and it will not reach the situation where the cotton net is processed once. As a result, it is impossible to make the non-woven fabric interact with a sufficient amount of water flow, and it is impossible to obtain a non-woven fabric with a clear pattern. On the other hand, when the distance between the two is long, the water flow after passing through the opening will expand, and it is still impossible to obtain a non-woven fabric with a target pattern.

The distance between the opening member and the nozzle, for example, can be set to 0.1 cm to 4.0 cm, in particular, can be set to 0.3 cm to 3.0 cm, More specifically, it can be set to 0.5 cm to 2.0 cm. For example, when the distance between the opening member and the primary processed cotton web is at the desired distance, the distance between the opening member and the nozzle is short. When the two are close, the opening member and the nozzle will contact, and the opening member or Wear or breakage of the nozzle. On the other hand, when the distance between the two is long, as mentioned above, the water sprayed from the nozzle will expand before passing through the opening, and part of it will be blocked by the part outside the opening, and cannot reach the primary processed cotton web. , Some non-woven fabrics with clear patterns cannot be obtained.

The distance between the nozzle and the primary processing web is the sum of the distance between the opening and the nozzle, the thickness of the opening member, and the distance between the opening and the primary processing web. The distance between the nozzle and the primary processed cotton web can be specifically set to 3.6 cm to 12.0 cm, particularly to 4.3 cm to 9.0 cm, and more particularly to 5.0 cm to 8.0 cm. If the distance between the nozzle and the primary processed cotton web is too short, damage, wrinkles, and fluff will occur in the primary processed cotton web. In addition, when the distance between the nozzle and the cotton web for the primary processing is too short, the water flow of excess energy will be given to the cotton web. The desired trick. If the distance between the nozzle and the primary processed cotton web is too long, a sufficient amount of water flow cannot act on the non-woven fabric, and a non-woven fabric with a clear pattern may not be obtained. In addition, if the distance between the nozzle and the primary processed cotton web is too long, the water flow will expand in the opening member before reaching the cotton web, its energy will be weakened, and a non-woven fabric with a clear pattern may not be obtained.

In Figure 10, the nozzle is schematically shown as an opening structure The positional relationship between the rotating drum of the piece, the pattern forming support, and the once-processed cotton net. As shown in the figure, when the drum 34 is used as the opening member, the rotation direction of the drum 34 is generally a forward direction consistent with the movement direction of the pattern forming support 30 (that is, the conveying direction of the primary processed cotton web 32) direction. In addition, the primary processed cotton net 32 loaded on the pattern forming support 30 is ejected from the nozzle 38 arranged in the rotating drum 34, and is subjected to the action of the water flowing through the opening 36 of the rotating drum 34, thereby forming an island shape. unit. In the drum 34, since water does not pass through parts other than the opening 36, an island-shaped part corresponding to the opening 36 is formed in the cotton mesh 32 of the primary processing. In the case of using the opening member 34 in the shape of a rotating cylinder, water other than the water flowing through the opening portion 36 may stay in the opening member 34 in some cases. Such water is preferably discharged to the outside. The water retained in the opening member 34 can be sucked by a nozzle, for example, or can be drained from a drainage opening provided in the opening member 34.

In the case of using the drum 34 as the opening member, the rotation speed of the drum 34 and the conveying speed of the cotton net 32 for the primary processing performed by the pattern forming support 30 are appropriately adjusted to form the desired islands. . Specifically, when the linear velocity of the rotating drum 34 is approximately the same as the conveying speed of the primary processed cotton web 32, the distance and interval between the island-shaped portions and the opening 36 formed in the drum 34 will be approximately the same. Roughly the same. When the linear speed of the rotating drum 34 is higher than the conveying speed of the cotton web 32 at one time, the islands will be denser (changes in pitch and interval are shorter). Or, when the linear speed of the rotating drum 34 is lower than the conveying speed of the support 30 forming the cotton web 32 at one time, the islands will be formed more sparsely (pitch, The interval change is longer).

The nozzles and water pressure ranges that can be used when forming islands are the same as when forming the first high-density region. The islands are usually formed by jetting water only once on one side of the cotton web that is processed at a time. The pressure during the formation of the islands can be particularly set to 1 MPa to 15 MPa, and more particularly can be set to 2 MPa to 10 MPa.

In the above, the method of forming the island-shaped portion (low-density area, second high-density area) from the first-time processing of the cotton fabric in advance has been described. If the method of fabricating the processed cotton net in advance, it is better because it can form distinct islands (low-density area and second high-density area) in the moderately entangled cotton net. In other forms, the production of the processed cotton net and the formation of the island-shaped portion may be performed at the same time. For example, the production of cotton net and the formation of islands can be carried out at the same time by the following method: the nozzles are arranged in one row or multiple rows on the outside of the drum, and the nozzles eject a lower energy and high pressure from one side. For fluid, a method of jetting a higher energy fluid from the inside of a rotating drum; a method of forming a pattern on the lower side of the support and impacting a high-pressure fluid with lower energy, while jetting a higher-energy high-pressure fluid from the inside of the rotating drum; at high temperatures Under the environment, the whole non-woven fabric is adhered, and high-energy, high-pressure fluid is injected from the inside of the drum.

In addition, in other forms, it is possible to produce a primary processed cotton web without high-pressure fluid entanglement treatment. For example, the primary processed cotton web can be produced by melting a part of the fiber (for example, the sheath component of the core-sheath composite fiber described previously) by heat treatment, etc., and then bonding the fibers to each other, or a suitable method can be used. Adhesive to make the fibers indirectly bond with each other Method of production. Or, the one-time processing cotton web can be made by combining the entanglement treatment by the high-pressure fluid and the subsequent treatment.

In the above method, a cotton web (hereinafter, also referred to as "secondary processed cotton web") in which the first high-density area and island-shaped portions (low-density area and second high-density area) are formed can be applied to remove moisture During the drying process, it is directly used as the non-woven fabric of this embodiment. When the secondary processed cotton web contains synthetic fibers, and part or all of the fiber surface of the synthetic fibers is formed of a resin with a relatively low melting point, such as polyethylene, a low-melting resin can be applied to heat the fibers. The indirect heat is then processed. The thermal bonding treatment is preferably carried out at a temperature at which the lowest melting point among the thermoplastic resins constituting the surface of the synthetic fiber will melt or soften. For synthetic fibers, for example, when part or all of the fiber surface is a single fiber or a composite fiber composed of polyethylene, the heat bonding treatment is preferably performed at a temperature of 130°C or more and 150°C or less. By adjusting the heat treatment temperature, the degree of thermal bonding can also be changed. The degree of thermal bonding affects the strength, softness, and touch of the non-woven fabric.

The heat bonding treatment can be combined with the drying treatment that removes moisture from the secondary processed cotton web. Alternatively, the thermal bonding treatment and the drying treatment may be performed separately. Thermal bonding can be implemented using a hot-air through-type heat treatment machine (also referred to as a vent-type heat treatment machine), a hot-air blowing heat treatment machine, an infrared heat treatment machine, or a heat roller (including a hot embossing roller) processing machine.

Adhesion using the constituent resin of the synthetic fiber as the connecting component can be carried out, for example, by irradiation with an electron beam or the like, or by ultrasonic welding. Or, the bonding between the fibers can also be done by using an adhesive. Implement.

The non-woven fabric of this embodiment forms a pattern by combining 3 different fiber density regions, which exerts a unique design effect. In addition, in the non-woven fabric of the present embodiment, the independent island-shaped portions form a pattern, and the second high-density regions intertwined with high fiber density are interspersed. Therefore, it is similar to the non-woven fabric in which the pattern is formed in stripes as in Patent Document 2. In comparison, the strength balance in the vertical and horizontal directions is good.

In addition, the non-woven fabric of this embodiment is adjusted by adjusting the shape and area of each low-density region and the ratio (area ratio) of the entire low-density region to the non-woven fabric, the shape and area of each island-like portion, and the total area of the island-like portion. The ratio (area ratio) of the non-woven fabric can be made the most suitable for the performance of the non-woven fabric. For example, by changing the shape, area, and area ratio of low-density regions and islands, when used as a surface material for absorbent articles, the tactile feel and liquid absorption properties can be adjusted appropriately. In the case of wiping paper, the wiping properties and handling properties can be adjusted appropriately.

The nonwoven fabric of this embodiment can be suitably used as a surface material of absorbent articles, such as a sanitary napkin and a sanitary pad, for example. When used as a surface material for absorbent articles, the low-density area is an entrance for menstrual blood and secretions to move to the side of the absorbent body, prompting these to move quickly to the absorbent body. Or, the non-woven fabric of this embodiment can be used as a tissue wipe, a human wipe, a towel, a face mask, a mask, a filter, or a cataplasm.

[Example]

Hereinafter, the non-woven fabric of this embodiment will be explained with examples.

(Example 1)

Prepare to use viscose rayon (trade name CD, made by Daiwabo Rayon (strand)) with a fineness of 1.7dtex and a fiber length of 40mm, and high-density polyethylene with a fineness of 1.7dtex and a fiber length of 51mm as the sheath component, and polypropylene as the sheath component Core sheath type composite fiber (trade name NBF(H)P, manufactured by Daiwabo Polytec (stock)). 80% by mass of rayon and 20% by mass of core-sheath composite fibers were mixed to produce a parallel cotton net ^{with a weight per unit area of approximately 40 g/m 2.}

This cotton web is subjected to water flow entanglement treatment to form the first high-density area.

The water flow entanglement process is to load the cotton web on a 90-mesh plain weave support composed of monofilaments with a wire diameter of 0.132mm. Use nozzles with nozzles with a hole diameter of 0.12mm at intervals of 0.6mm to face one side of the cotton web. A columnar water flow of 2.5 MPa was injected once, and a columnar water flow of 2.5 MPa was injected once to the other side. At this time, the speed of the support is 4m/min, and the distance between the nozzle and the cotton net is 20mm.

Next, a water flow entanglement process for forming islands (a low-density region and a second high-density region) is performed.

The water flow entanglement process will form the first high-density area of the cotton web, and load it on a 25-mesh plain weave support composed of monofilaments with a diameter of 0.7mm (the warp and weft densities are both 25 strands/inch) At the same time, prepare a circular opening with a diameter of 5mm with a diagonal spacing of 15mm, a diagonal spacing of 10mm, a horizontal spacing of 10mm, and a horizontal spacing of 5mm. A rotating drum arranged in the shape of a thousand birds, in which nozzles are arranged, and water jets are sprayed from the nozzles. The drum is a metal plate having a thickness of 3 mm by punching and forming an opening. The distance between the nozzle and the net is 40mm, the distance between the nozzle and the drum is 20mm, and the distance between the cotton net and the drum is 20mm.

The nozzle is of the same specification as the one used to form the first high-density zone. The pressure of the columnar water stream is set to 2MPa, and the columnar water stream is sprayed once on one side of the cotton web. During the water flow entanglement process, the drum is rotated at a speed of 4.3 rpm, and the support will be moved at a speed of 4 m/min. In order to make the columnar water flow only pass through the opening of the drum and hit the cotton net on the support, the water flow entanglement is implemented only in the part corresponding to the opening. In addition, the support is made of yarns that are thicker than the support used when forming the first high-density region, and if relatively large protrusions are formed at the weaving points, the fibers on the protrusions of the support will flow away due to the water flow. Move around to form a low-density area. At the same time, the moving fibers are entangled to form a second high-density area.

In the obtained non-woven fabric, the low-density areas are almost all perforations, and the vertical spacing is 3mm, the horizontal spacing is 2mm, the vertical spacing is 2mm, and the horizontal spacing is 1mm, the diagonal spacing is 2mm, and the diagonal direction is 2mm. Arranged in a chidori shape with an interval of 1mm. In addition, each island has about 7 low-density regions and is a circle with a diameter of about 5mm. The islands are spaced at 20mm in the longitudinal direction and 8.3mm in the transverse direction, 11mm in the longitudinal direction and 11mm in the transverse direction. 6mm, 10.8mm in the diagonal direction, and 5.8mm in the diagonal direction, arranged in a chidori shape. Also, in the island part occupied by the non-woven fabric The area ratio is 23.6%, and the area ratio in the low-density area occupied by non-woven fabrics is 3.3%.

After the islands are formed, the cotton web is dried using a dryer set at 80°C, and then a hot air through-type heat treatment machine set at 135°C is used to melt or soften the polyethylene of the core-sheath composite fiber to make the fiber Heat to each other. Drying and thermal bonding are performed for 10 seconds. The photograph showing the surface of the obtained non-woven fabric is shown in Fig. 3.

(Example 2)

In the water flow entanglement process used to form islands (low-density area and second high-density area), in addition to the use of circular openings with a diameter of 5 mm at a diagonal pitch of 9.6 mm, and a diagonal Except for the drums arranged in a chidori shape with an interval of 3.2 mm, a lateral interval of 10 mm, and a lateral interval of 5 mm, the rest was performed in the same order as in Example 1 to obtain a non-woven fabric.

In the obtained non-woven fabric, the low-density areas are almost all perforations, and the vertical spacing is 3mm, the horizontal spacing is 2mm, the vertical spacing is 2mm, the horizontal spacing is 1mm, and the diagonal direction spacing is 2mm. Arranged in a chidori shape with an interval of 1mm. In addition, each island-shaped portion has about 7 low-density regions and is circular with a diameter of about 5 mm. The island-shaped portions have a vertical distance of 11.1 mm and a horizontal distance of 8.3 mm, a vertical distance of 6.1 mm, and a horizontal distance. It is formed by arraying in a chidori shape with an interval of 3.3mm, a distance of 6.9mm in the diagonal direction, and a distance of 1.9mm in the diagonal direction. In addition, the area ratio of the island-shaped portion occupied by the non-woven fabric is 42.3%, and the area ratio of the low-density region occupied by the non-woven fabric It is 11.8%.

(Example 3)

In the water flow entanglement process used to form islands (low-density areas and second high-density areas), apart from using a diamond-shaped opening with a vertical diagonal of 15 mm and a horizontal diagonal of 15 mm in a diagonal direction Except for the drums arranged in a square arrangement with a pitch of 53.2 mm, a diagonal interval of 47.6 mm, a lateral pitch of 32.4 mm, and a lateral interval of 18.0 mm, the rest was performed in the same order as in Example 1 to obtain a non-woven fabric.

In the obtained non-woven fabric, the low-density areas are almost all perforations, and the vertical spacing is 3mm and the horizontal spacing is 2mm, the vertical spacing is 2mm, and the horizontal spacing is 1mm, and the diagonal spacing is 2mm. It is formed by arraying in a chidori shape with an interval of 1mm in the direction. In addition, each island has about 24 low-density regions, and is a rhombus with a 15mm diagonal in the direction and 15mm in a horizontal diagonal, with a vertical pitch of 27.2mm, a horizontal pitch of 27.3mm, and a vertical interval. 12.1mm and 12.2mm in the horizontal direction, 38.3mm in the diagonal direction, and 28.1mm in the diagonal direction. In addition, the area ratio of the island-shaped portion occupied by the non-woven fabric is 16.0%, and the area ratio of the low-density region occupied by the non-woven fabric is 6.1%.

(Example 4)

In the water flow entanglement process used to form islands (low-density areas and second high-density areas), in addition to the use of circular openings with a diameter of 5 mm at a diagonal pitch of 11.6 mm, and a diagonal Arranged in a pattern of 5.6mm spacing, 10mm horizontal spacing, and 5mm horizontal spacing. Except for the shape of the rotating drum, the rest was performed in the same order as in Example 1 to obtain a non-woven fabric.

In the obtained non-woven fabric, the low-density areas are almost all perforations, and the vertical spacing is 3mm, the horizontal spacing is 2mm, the vertical spacing is 2mm, and the horizontal spacing is 1mm, the diagonal spacing is 2mm, and the diagonal direction is 2mm. It is formed by arranging in a chidori shape with an interval of 1mm. In addition, each island has about 7 low-density regions and is a circle with a diameter of about 5mm, and has a vertical spacing of 14.3mm, a horizontal spacing of 8.3mm, a vertical spacing of 9.3mm, and a horizontal spacing of 3.3mm. It is formed by arranging in a chidori shape with a pitch of 8.3mm in the diagonal direction and a pitch of 3.3mm in the diagonal direction. In addition, the area ratio of the island-shaped portion occupied by the non-woven fabric is 32.9%, and the area ratio of the low-density region occupied by the non-woven fabric is 9.2%.

(Comparative example 1)

Except that the water flow entanglement process for forming the second high-density region was not performed, the rest was performed in the same order as in Example 1 to obtain a non-woven fabric.

(Comparative example 2)

Except that the water flow entanglement process for forming the second high-density region is performed without using the opening member, the rest is the same procedure as in Example 1 to obtain the non-woven fabric. In the obtained nonwoven fabric, low-density regions were formed on the entire surface, but islands were not formed. The area ratio of the low-density region in the non-woven fabric is 28.0%.

(Comparative example 3)

Operate in the same order as in Example 1 to form the first high density After the area, use the nozzle that has blocked a part of the nozzle to implement the water flow entanglement treatment. Specifically, a part of the nozzle is blocked in such a way that there are alternately an area of about 5 mm where the nozzle is not clogged and an area of about 16.5 mm where the nozzle is clogged. In addition, the support is the same as the user when the second high-density area is formed in Example 1, and the water pressure and the speed of the support are set to be the same as those when the second high-density area in Example 1 is formed. The speed of the support is the same. Thus, the drying treatment and the thermal bonding treatment were performed in the same manner as in Example 1, and a non-woven fabric was obtained. In the obtained nonwoven fabric, a stripe-like pattern in which rows formed by the low-density regions and the second high-density regions and the rows of the first high-density regions are alternately arranged in the horizontal direction is obtained. In Comparative Example 3, the ratio of the low-density area to the entire nonwoven fabric was set to be the same as that of Example 1.

(Comparative Example 4)

In the water flow entanglement treatment after the formation of the first high-density area, except for the nozzles that block part of the nozzles in such a way that the area where the nozzles are not clogged is about 2mm and the area where the nozzles are clogged is about 6.5mm alternately, the rest is used with A non-woven fabric was produced in the same order as in Comparative Example 3. In addition, in Comparative Example 4, the ratio of the low-density area to the entire nonwoven fabric was also set to be the same as that of Example 1.

(Comparative Example 5)

In the water flow entanglement process used to form islands (low-density areas and second high-density areas), in addition to the use of circular openings with a diameter of 5 mm at a diagonal pitch of 7.8 mm, the diagonal Arranged in a pattern of 1.7mm spacing, 7.3mm horizontal spacing, and 1.5mm horizontal spacing The non-woven fabric was obtained in the same order as in Example 1 except for the shape of the rotating drum.

In the obtained non-woven fabric, the low-density areas are almost all perforations, and the vertical spacing is 3mm, the horizontal spacing is 2mm, the vertical spacing is 2mm, and the horizontal spacing is 1mm, the diagonal spacing is 2mm, and the diagonal direction is 2mm. It is formed by arranging in a chidori shape with an interval of 1mm. In addition, each island has about 7 low-density regions and is a circle with a diameter of about 5mm, with a vertical spacing of 10mm, a horizontal spacing of 6mm, a vertical spacing of 5mm, and a horizontal spacing of 1mm, in the diagonal direction. It is formed by arranging in a chidori shape with a pitch of 5.6mm and an interval of 1mm in the diagonal direction. In addition, the area ratio of the island-shaped portion occupied by the non-woven fabric is 62.4%, and the area ratio of the low-density region occupied by the non-woven fabric is 17.6%.

Regarding the nonwoven fabrics obtained in Examples 1 to 4 and Comparative Examples 1 to 5, the following physical properties were evaluated by the method described below. The evaluation results are shown in Table 1.

<breaking strength, breaking elongation, stress at 10% elongation>

According to JIS L 1096 6.12.1 A method (strip method), a constant-speed tensile type tensile testing machine is used, and the specimen is applied to the tensile tester under the conditions of 5 cm in width of the specimen, 10 cm in the clamping interval, and 30 ± 2 cm/min. The tensile test measures the load value (breaking strength) at the time of cutting, the elongation at break, and the stress at 10% elongation. The tensile test was performed using the longitudinal direction (MD direction) and the transverse direction (CD direction) of the nonwoven fabric as the tensile direction. The evaluation results are all expressed as the average of the values measured at 3 points of the sample.

<Designability>

The design of the obtained non-woven fabric was evaluated based on the following criteria.

A: The boundary between adjacent islands and islands is clear, and the pattern shown by the islands can be fully recognized.

B: The boundary between the adjacent island-shaped portion and the island-shaped portion is slightly clear, and the pattern shown by the island-shaped portion can be recognized.

C: The boundary between the adjacent island-shaped portion and the island-shaped portion is unclear, and the pattern shown by the island-shaped portion cannot be recognized.

Compared with Comparative Examples 1 and 2, the non-woven fabrics of Examples 1 to 4 have greater stress at 10% elongation. This is because, compared to Comparative Example 1, since Examples 1 to 4 are subjected to the water flow entanglement treatment to form the second high-density region, the entanglement of the fibers is performed only according to the corresponding components. In addition, it is estimated that in Comparative Example 2, a region with a high fiber density between the low-density region and the low-density region is formed on the entire surface. As a result, the strength is lower than that caused by the formation of the low-density region, and the fiber density is high. The strength increase brought by the area becomes more advantageous, so it is stretched at 10% The stress becomes higher than that of Comparative Example 1. In the nonwoven fabrics of Examples 1 to 4, the area ratio of the low-density region is smaller than that of the low-density region of Comparative Example 2, and the second high-density region formed between the low-density regions has a higher fiber density In this area, the fibers are firmly entangled with each other, so the increase in strength caused by the second high-density area becomes more advantageous. It is believed that the stress at 10% elongation is significantly greater than that of Comparative Example 2. To improve. In addition, when a non-woven fabric is provided as a surface material of an absorbent article or a wipe paper for human use, the non-woven fabric is often elongated by about 10% during processing or use. Therefore, the stress at 10% elongation is used here. Compare the strength of non-woven fabrics.

Compared with Comparative Example 1, the non-woven fabrics of Examples 1 to 4 have an increase in stress at 10% elongation obtained by forming a pattern, which can be recognized both in the longitudinal direction and the transverse direction. On the other hand, the nonwoven fabrics of Comparative Examples 3 and 4 did not show an increase in stress at 10% elongation in the transverse direction compared to the case of Comparative Example 1. This is because, in Examples 1 to 4, the islands forming the pattern are scattered in the non-woven fabric. Unlike Comparative Examples 3 and 4, the pattern-forming part (the part where the low-density area is gathered) is in the non-woven fabric. The vertical or horizontal is caused by discontinuities. The non-woven fabric of Comparative Example 5 has a large area ratio of the island-shaped portion, and therefore, the appearance design is poor. In addition, the stress system at 10% elongation of Comparative Example 5 is smaller than the stress at elongation of Examples 1 to 4. This is because the area ratio of the low-density region of Comparative Example 5 is greater than the area ratio of the low-density regions of Examples 1 to 4. In addition, among Examples 1 to 4, Example 2 has the lowest stress at 10% elongation. It is believed that the area ratio of the low-density region of Example 2 is larger than that of Examples 1, 3, and 4.

Regarding the non-woven fabrics of Examples 1 to 2 and Comparative Example 5, the cross-section of the first high-density region and the island-shaped portion was observed with an electron microscope to obtain the thickness, and the thickness was obtained from the thickness of the non-woven fabric and the weight per unit area of the non-woven fabric The fiber density of the first high-density area and the second high-density area. The thickness of the non-woven fabric is measured at 4 positions for each area, and after calculating the fiber density for each of the 4 positions, the average value of these is taken as the fiber density of each area. As a result, in the nonwoven fabric of Example 1, the fiber density of the first high-density region was 0.080 g/cm ³ , and the fiber density of the second high-density region was 0.089 g/cm ³ . In the nonwoven fabric of Example 2, the fiber density of the first high-density region was 0.077 g/cm ³ , and the fiber density of the second high-density region was 0.092 g/cm ³ . In the nonwoven fabric of Comparative Example 5, the fiber density of the first high-density region was 0.082 g/cm ³ , and the fiber density of the second high-density region was 0.093 g/cm ³ .

The disclosure of the present invention includes the following aspects.

(Aspect 1)

A pattern-attached non-woven fabric with a pattern with low-density areas, a first high-density area, and a second high-density area, wherein the low-density areas are plurally assembled to form an island, and the aforementioned one In the island-shaped portion, the second high-density region is formed at least between the low-density region and the low-density region, the first high-density region is formed between the island-shaped portion and the island-shaped portion, and the first 1 The fiber density of the high-density area is less than the fiber density of the second high-density area, The fiber density of the low-density region is smaller than the fiber density of the first high-density region, or the low-density region is an open portion, and the total area of the low-density region is From 0.1% to 12%, the total area of the island-shaped portion is 1% to 45% relative to the total area of the non-woven fabric with the pattern.

(Aspect 2)

The pattern-attached non-woven fabric of aspect 1, wherein the low-density area is a concave portion or an open-hole portion, and in the island-shaped portion, the plurality of low-density areas are formed in a regular pattern.

(Aspect 3)

Such as pattern 2 non-woven fabric with patterns, wherein the aforementioned regular patterns are selected from dot pattern, herringbone pattern, checkerboard pattern, lattice pattern, thousand bird pattern, diagonal stripe pattern, wave pattern and zigzag pattern. At least one pattern in the group formed by the pattern pattern.

(Aspect 4)

A patterned non-woven fabric such as any one of patterns 1 to 3, wherein each of the aforementioned low-density regions has an area of 0.03mm ² to 20mm ² , and the aforementioned low-density regions have a pitch of 0.1mm in at least one direction To 50mm, the spacing in at least one direction is 0.1mm to 50mm in a thousand bird-shaped arrangement or a square arrangement.

(Aspect 5)

The pattern-attached non-woven fabric such as any one of the aspects 1 to 4, wherein each area of the aforementioned island-shaped portion is 1.0 mm ² to 18000 ^{mm 2} .

(Aspect 6)

A pattern-attached nonwoven fabric such as any one of patterns 1 to 5, wherein the aforementioned island-like portions are arranged in a chidori shape with a distance of 5mm to 100mm in at least one direction and a distance of 1mm to 100mm in at least one direction, It is arranged in a square arrangement or a diamond pattern.

(Aspect 7)

A pattern-attached non-woven fabric such as any one of the aspects 1 to 6, wherein, in the aforementioned non-woven fabric, the fibers are intertwined with each other.

(Aspect 8)

A method for manufacturing a pattern-attached non-woven fabric, the pattern-attached non-woven fabric has a low-density area, a first high-density area, and a second high-density area, wherein the low-density areas are plurally assembled to form an island shape Section, the fiber density of the first high-density area is less than the fiber density of the second high-density area, the fiber density of the low-density area is less than the fiber density of the first high-density area, or the low-density area is open pores The manufacturing method includes: preparing a cotton web; performing entanglement and/or subsequent processing on the entire surface of the cotton web to form a first high-density area; and placing the cotton web on a convex portion selected from, At least one of the recesses and the openings is provided on the support, and a member having a plurality of openings is arranged between the cotton net and the nozzle that sprays the high-pressure fluid, and the parts other than the openings do not penetrate the high-pressure fluid (Hereinafter referred to as "opening member"), and in this state, the aforementioned high-pressure fluid is sprayed from the aforementioned nozzle and only passes through The high-pressure fluid in the opening part impacts the cotton net to form a low-density area and a second high-density area.

(Aspect 9)

The method of manufacturing a pattern-attached nonwoven fabric of aspect 8, wherein the opening member is a drum with an opening, the distance between the drum and the net is 0.5 cm to 5.0 cm, and the nozzle is arranged on the In the drum, during the injection of the high-pressure fluid, the rotating drum is rotated.

(Aspect 10)

The manufacturing method of the patterned non-woven fabric of aspect 8 or 9, wherein the high-pressure fluid is a high-pressure liquid.

[Industrial availability]

In the patterned nonwoven fabric of this embodiment, the island-shaped portion composed of a plurality of low-density regions and a second high-density region formed between the low-density regions is formed where the fiber density is higher than that of the second high-density region. It is formed in the first high-density area with a smaller area, and exerts a high design effect, so it can be used for products that are susceptible to users' eyes, such as surface materials for absorbent articles or wipes for humans, wipes for objects, etc. .

10.10A: low density area

12: The first high-density area

14: The second high-density area

20: Island

100: non-woven

Claims (9)

A pattern-attached non-woven fabric that has a low-density area, a first high-density area, and a second high-density area. In the one island-shaped portion, the second high-density region is formed at least between the low-density region and the low-density region, and the first high-density region is formed between the island-shaped portion and the island-shaped portion The fiber density of the first high-density area is smaller than the fiber density of the second high-density area, and the island-shaped portion or the pattern formed by the multiple number of the island-shaped portions has a pitch of 5mm to 100mm in all directions. The direction interval is 1mm to 100mm in a thousand birds arrangement, a square arrangement or a diamond pattern. The fiber density of the low-density area is less than the fiber density of the first high-density area, or the low-density area is an open hole , With respect to the total area of the non-woven fabric with patterns, the total area of the low-density region is 0.1% to 12%, and the total area of the island-shaped portions is from 1% to 12% relative to the area of the non-woven fabric with patterns. 45%. The pattern-attached non-woven fabric described in the first item of the scope of patent application, wherein the aforementioned low-density area is a concave portion or an open-hole portion, and in the aforementioned island-shaped portion, the aforementioned low-density area grouped in plural forms a regular pattern. kind. For example, the non-woven fabric with a pattern described in item 2 of the scope of patent application, wherein the aforementioned regular pattern is selected from dot pattern, herringbone pattern, checkerboard pattern, lattice pattern, and houndstooth pattern. pattern), diagonal stripe pattern, wave pattern and zigzag pattern at least one pattern. The pattern-attached non-woven fabric as described in item 1 of the scope of patent application, wherein each of the aforementioned low-density regions has an area of 0.03mm ² to 20mm ² , and the aforementioned low-density regions have a pitch of 0.1mm to 50mm in at least one direction , At least one direction is arranged in a thousand bird-shaped arrangement or square arrangement with an interval of 0.1mm to 50mm. The pattern-attached non-woven fabric as described in item 1 of the scope of patent application, wherein the area of each of the aforementioned island-shaped portions is 1.0 mm ² to 18000 ^{mm 2} . The non-woven fabric with a pattern as described in item 1 of the scope of patent application, wherein the aforementioned island-shaped parts are circular, elliptical, cloud-shaped, polygonal with more than three sides, star-shaped, flower, tri-leaf (Clover ), heart or text. The pattern-attached non-woven fabric as described in item 1 of the scope of patent application, wherein, in the aforementioned non-woven fabric, the fibers are intertwined with each other. A method for manufacturing a pattern-attached non-woven fabric, the pattern-attached non-woven fabric has a low-density area, a first high-density area, and a second high-density area, wherein the low-density areas are plurally assembled to form an island shape Section, the fiber density of the first high-density zone is smaller than that of the previous The fiber density of the second high-density area, the fiber density of the low-density area is less than the fiber density of the first high-density area, or the low-density area is an open portion; the manufacturing method includes: preparing a cotton net; Entangling and/or subsequent processing is performed on the entire surface of the cotton web to form a first high-density area; and placing the cotton web on a support having at least one selected from the group consisting of convex portions, concave portions, and openings Simultaneously with the above, a member with a plurality of openings is arranged between the cotton net and the nozzle spraying high-pressure fluid, and parts other than the openings will not penetrate the high-pressure fluid member (hereinafter referred to as "opening member"). In this state, the high-pressure fluid is sprayed from the nozzle and only the high-pressure fluid passing through the opening is impacted on the cotton net to form a low-density area and a second high-density area; wherein the opening member has an opening. A drum, the distance between the drum and the cotton net is 0.5 cm to 5.0 cm, the nozzle is arranged in the drum, and the drum is rotated during the injection of the high-pressure fluid. The method for manufacturing a pattern-attached non-woven fabric as described in item 8 of the scope of patent application, wherein the high-pressure fluid is a high-pressure liquid.

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