JP5144411B2 - Non-woven - Google Patents

Description

  The present invention relates to a non-woven fabric having a ridge groove structure and an opening in a groove portion. This nonwoven fabric is particularly suitably used as a surface sheet for absorbent articles.

  As a conventional technique related to a nonwoven fabric having a ridge groove structure, for example, a technique described in Patent Document 1 is known. This document describes a surface sheet of an absorbent article in which a trough and a peak facing the liquid receiving side extend in the longitudinal direction and are formed in a wave shape in the width direction, which is a direction orthogonal to the longitudinal direction. ing. This surface sheet is made of non-woven fabric, and in the mountain portion, rough portions having low density of fibers constituting the surface sheet and dense portions having high density are alternately formed in the longitudinal direction. According to Patent Document 1, according to the technique described in the document, since the surface sheet is curved at each rough portion in the peak portion, it is prevented that the surface sheet is forcibly bent at a dense portion other than the rough portion. Have been described.

  Apart from the technique described in Patent Document 1, the present applicant previously formed a number of strip-like top portions that are discontinuous with respect to the non-woven fabric having a ridge groove structure, and a recess formed in a strip shape in the space between the top portions. The surface sheet of the absorbent article formed from the innumerable strip-shaped bottom part and the strip | belt-shaped wall part which each connects a top part and a bottom part was proposed (refer patent document 2). The surface sheet described in the document is made of nonwoven fabric. In this surface sheet, an opening is provided at the bottom. Moreover, the top part in this surface sheet is formed in the uneven | corrugated shape of the zigzag-like both-sides edge of the strip | belt-shaped top surface.

JP 2001-137284 A JP-A-5-317358

  An object of the present invention is to provide a nonwoven fabric that has improved various performances, particularly as a surface sheet of an absorbent article, as compared with the above-described prior art nonwoven fabrics.

The present invention is formed by intermittently arranging a large number of convex portions in a row, extending between a plurality of ridges extending in a unidirectional manner and adjacent ridge portions, and in the same direction as the ridge portion A non-woven fabric having a large number of grooves extending in the groove portion and having openings formed in the groove portions,
The ridge has a recess having a height lower than that of the protrusion between adjacent protrusions in the extending direction, and the ridge has a fiber density at the recess and a fiber density at the bottom of the protrusion. A non-woven fabric that is substantially equal is provided.

In addition, the present invention provides a large number of protrusions that are formed by intermittently arranging a plurality of protrusions in a row, and that are located between adjacent flanges and that are in the same direction as the flanges. A non-woven fabric having a plurality of grooves extending in the direction, and having openings formed in the grooves,
The collar portion has a recess having a height lower than that of the protrusion between adjacent protrusions in the extending direction,
Provided is a nonwoven fabric in which the ridge portion extends in a zigzag shape and the concave portion is located at the bending point of the zigzag.

  According to the nonwoven fabric of the present invention, when this is used as, for example, a surface sheet of an absorbent article, due to the thickness difference between the heel and the groove, the area where the surface sheet contacts the wearer's skin is reduced, The occurrence of stuffiness and the occurrence of skin troubles resulting therefrom are effectively prevented. In particular, the contact area is further reduced by forming a large number of recesses in the collar by recessing the collar. Moreover, this recessed part also contributes to the smooth bending of a surface sheet, and it becomes difficult to generate | occur | produce the wrinkles resulting from the bending of a surface sheet. Furthermore, since this recessed part contributes also to the improvement of the air | flow distribution along the surface direction of a surface sheet, generation | occurrence | production of the stuffiness and the occurrence of the skin trouble resulting from this are also prevented effectively.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The principal part enlarged view in planar view of 1st Embodiment of the nonwoven fabric of this invention is shown by Fig.1 (a). FIGS. 1B and 1C are a cross-sectional view taken along the line bb and a cross-sectional view taken along the line cc in FIG. The nonwoven fabric of this embodiment assumes the use as a surface sheet of an absorbent article mainly. Therefore, in the following description, the nonwoven fabric of this embodiment is also referred to as a “surface sheet”.

  1 (a) to 1 (c), the topsheet 10 has a first surface 10a and a second surface 10b opposite to the first surface 10a. The 1st surface 10a is a surface which faces a wearer's skin side, when the surface sheet 10 is integrated in absorbent articles, such as a sanitary napkin and a disposable diaper. The 2nd surface 10b is a surface which faces the absorber side of an absorbent article. The topsheet 10 has a large number of flanges 20 extending in one direction Y. Moreover, the topsheet 10 has a large number of groove portions 30 extending in the same direction Y as the flange portion 20 between the adjacent flange portions 20. The flange portions 20 and the groove portions 30 are alternately arranged over a direction X orthogonal to the extending direction Y thereof. The flange portion 20 is configured from a relatively thick portion of the topsheet 10, and the groove portion 30 is configured from a relatively thin portion of the topsheet 10. As a result, the substantial thickness of the flange portion 20 is larger than the thickness of the groove portion 30. Here, the substantial thickness means not the length (apparent thickness) from the back surface of the top sheet 10 to each uppermost part, but the length of the portion where the fibers of the top sheet 10 are present.

  As shown in FIG. 1A, the collar portion 20 has a large number of convex portions 23 arranged intermittently in a row and extends in a collar shape in one direction (the direction indicated by Y in FIG. 1A). It is formed by that. Each convex portion 23 has an elongated shape having a width and a length larger than the width. And the collar part 20 has the recessed part 22 whose height is lower than the convex part 23 between the convex parts 23 adjacent in the direction (direction shown by Y in FIG. 1A) where the collar part 20 extends. Therefore, in each collar part 20, the convex part 23 and the recessed part 22 are located alternately along the extension direction (direction shown by Y in FIG. 1A).

  As shown in FIG.1 (c), the collar part 20 is the position of the convex part 23, and the cross section in the direction (direction shown by X in the figure) orthogonal to the direction where this collar part 20 is extended is 1st. On the side of the surface 10a, it has an outline that draws a smooth convex curve upward. The side of the second surface 10b is substantially flat as shown in FIG. 1C, or has a contour that draws a smooth and gentle curve convex downward. The first surface 10a side at the position of the convex portion 23 is raised higher than the second surface 10b side, and this is periodically continuous. Thereby, the first surface 10a side at the position of the convex portion 23 has a waveform shape along the X direction. On the other hand, as shown in FIG. 1 (b), the flange portion 20 has a substantially flat cross section in the X direction at the position of the recess 22 on the first surface 10 a side. Therefore, when the 1st surface 10a side of the surface sheet 10 touches a wearer's skin, the top part 21 of the convex part 23 and the area | region of the vicinity will contact partly, and it is by the stuffiness resulting from a full surface contact. Stickiness and irritation caused by rubbing are reduced. Moreover, it becomes difficult for the liquid excreted from the wearer to adhere to the wearer's skin.

  The convex part 23 and the concave part 22 in the collar part 20 are filled with the constituent fibers of the topsheet 10. That is, there is no cavity in the convex portion 23 and the concave portion 22. Similarly, a portion of the groove portion 30 where an opening 31 described later is not formed is filled with constituent fibers of the topsheet 10. However, as will be described later, the fiber amount of the flange portion 20 is different from the fiber amount of the groove portion 30.

  As shown in FIG.1 (c), the convex part 23 of the collar part 20 has the top part 21 in the 1st surface 10a side in the cross section in a X direction, and the substantial thickness is the largest in this site | part. . Then, with respect to the X direction, the substantial thickness gradually decreases as the distance from the top portion 21 increases. Accordingly, the surface sheet 10 has a substantial thickness periodically changed when viewed along the X direction in the convex portion 23 of the flange portion 20. In the topsheet 10 of the present embodiment, there is no clear boundary between the flange portion 20 and the groove portion 30, and in general, a portion having the smallest substantial thickness located between the two top portions 21 adjacent to each other in the X direction and A portion in the vicinity thereof becomes the groove 30. When the boundary between the flange portion 20 and the groove portion 30 is clearly defined, the position of the apparent thickness at the top portion 21 of the flange portion 20 is defined as the boundary portion between the flange portion 20 and the groove portion 30.

  The apparent thickness D1 (see FIG. 1C) of the convex portion 23 in the heel portion 20 is preferably 0.3 to 5 mm, more preferably 0.5 to 5 from the viewpoint of improving the touch of the topsheet 10. 2.5 mm. The height difference D2 (see FIG. 1 (c)) between the convex portion 23 and the groove portion 30 is preferably 0.1 to 3 mm from the viewpoint of enhancing the cushioning property and air permeability of the topsheet 10 and controlling the diffusion of the liquid. 0.3 to 2 mm is more preferable. The thickness and height difference D of the flange part 20 and the groove part 30 are measured by using a microscope VH-8000 (manufactured by Keyence) and observing the cross section of the topsheet 10 at 50 to 200 times. The cross section is obtained by cutting the top sheet 10 using a feather razor (part number FAS-10, manufactured by Feather Safety Razor Co., Ltd.).

  The width of the heel portion 20 in the X direction of the topsheet 10 is preferably 1 to 10 mm, and more preferably 2 to 5 mm, from the viewpoint of touch and absorbency. From the same viewpoint, the width of the groove 30 in the X direction of the topsheet 10 is preferably 0.5 to 7 mm, and preferably 1 to 3 mm. In the present embodiment, the flange portion 20 and the groove portion 30 are formed with substantially the same width. However, the present invention is not limited to this, and for example, the width of the flange portion 20 in the central region in the X direction of the topsheet 10 The width of the portion 20 may be wider. Or it can be set as a desired form, such as making the width | variety of the collar part 20 and the groove part 30 random.

  The width of the convex portion 23 in the X direction of the topsheet 10 is the same as the width of the flange portion 20 described above. On the other hand, the length of the convex portion 23 in the Y direction of the topsheet 10 is preferably 5 to 30 mm, and more preferably 10 to 25 mm. In this connection, the ratio (length / width) between the length and width of the convex portion 23 is preferably 0.5 to 25, particularly 1 to 10.

  The substantial thickness of the convex portion 23 of the flange portion 20 is preferably 60 to 100%, particularly 70 to 100% of the apparent thickness. The substantial thickness itself of the convex portion 23 is preferably 0.2 to 4 mm, particularly preferably 0.3 to 3 mm, at the largest portion (top portion 21). When the convex part 23 of the collar part 20 has such a thickness, the convex part 23 becomes difficult to fall down, the cushioning property of the surface sheet 10 is improved, and the liquid absorbability (liquid passing property) is also improved. Further, when the substantial thickness of the convex portion 23 is thinner than the apparent thickness, specifically 90% or less, the absorbent article is deformed into a curved shape when the absorbent article having the topsheet 10 is used. However, it is prevented that the clearance gap produced between the surface sheet 10 and an absorber becomes large. Moreover, the surface sheet 10 fits a wearer's skin flexibly. In addition, it is preferable that the substantial thickness of the groove part 30 is 0.1-1 mm.

  When viewed along the direction indicated by X in FIG. 1 (a), the recesses 22 in the flanges 20 form a recess array 22A in which the recesses 22 in each of the flange sections 20 are connected in a straight line, and the recess array 22A. Are arranged at predetermined intervals along the Y direction of the topsheet 10. As shown in FIG. 1B, the thickness of the flange portion 20 in the concave portion 22 is substantially equal to the thickness of the groove portion 30. Therefore, the first surface 10a side of the topsheet 10 along the recess row 22A is substantially flat.

  The length of the concave portion 22 along the longitudinal direction of the collar portion 20, in other words, the distance between the convex portions 23 adjacent in the Y direction is 0.5 to 5 mm, particularly 1 to 3 mm. Maintaining the height of the top portion while maintaining cushioning properties and flexibility, enhancing the effect of reducing the stickiness due to the decrease in the contact area due to the concave portion 22 and the airflow in the planar direction on the first surface 10a side of the topsheet 10 It is preferable from the point of improving the property. In addition, the pitch P1 along the Y direction of the recess rows 22A is constant, and is 1 to 10 mm, particularly 2 to 5 mm. The amount of crushing) is constant, which is preferable from the viewpoints of stabilizing cushioning properties and flexibility, and further absorbability, and ease of manufacturing control.

  By forming the flange portion 20 having the convex portion 23 and the concave portion 22 as described above, the topsheet 10 is easily bent with the concave portion row 22A as a flexible shaft. Therefore, when the absorbent article provided with the topsheet 10 is viewed from the side surface, the absorbent article easily bends (bends) concavely toward the topsheet 10 side in the longitudinal direction. As a result, the discomfort caused by wrinkles that occur irregularly on the top sheet and the occurrence of liquid flow are suppressed, the absorbent article and the wearer's body are easily fitted, and the top sheet 10 and the absorbent body are not easily separated. Become. Thereby, the permeability | transmittance of the excreted liquid and the transferability of the liquid from the surface sheet 10 to an absorber become favorable. Further, when the absorbent article conforms to the curved shape of the wearer's body, the concave portion 22 is formed on the skin-facing surface side of the topsheet 10, and the concave portion 22 functions as a flexible shaft (region). At 22, the absorbent article bends and the tops of the flanges 20 formed on both sides in the longitudinal direction of the absorbent article sandwiching the recess 22 are close to each other. As a result, the gaps of the recesses 22 are filled, so that the liquid can be more easily taken up. On the other hand, in a part facing the excretion part of the wearer in the absorbent article, although there is an individual difference, the gap due to the concave part 22 is curved so as to be maintained or slightly widened, so that the air permeability can be kept high. In addition, in the front part and the rear part of the absorbent article, even when these parts are along the curved shape of the wearer's body, the amount of movement of the topsheet 10 is larger as the part closer to the top of the convex part 23, A space is left in the portion close to the concave portion 22, and the air permeability in the width direction is not lost.

  Moreover, in the collar part 20, the fiber density in the recessed part 22 and the fiber density in the bottom part 24 (refer FIG.1 (c)) of the convex part 23 are substantially equal. As a result, the liquid permeability of the top sheet 10 is improved, and the liquid residue hardly occurs on the top sheet 10. In the present specification, the fiber density is the amount of fiber present in a unit volume. The bottom 24 of the convex portion 23 is a portion of the convex portion 23 whose position in the thickness direction corresponds to the concave portion 22. That is, it is a part of the convex part 23 excluding the part protruding upward from the upper surface of the concave part 22. In order to make the fiber density in the concave portion 22 substantially equal to the fiber density in the bottom portion 24 of the convex portion 23, for example, in the manufacturing process of the topsheet 10 using the apparatus 100 shown in FIG. What is necessary is just to adjust the grade of the spray of the fluid using 130 suitably.

  Regarding the convex part 23, there is no restriction | limiting in particular in the magnitude relationship of the fiber density of the bottom part 24, and the fiber density of the upper part 25 (refer FIG.1 (c)). From the viewpoint of obtaining a soft feel and taking the liquid between the top sheet and the skin and moving the liquid from the upper part 25 to the bottom part 24 to enhance dry feeling and prevent skin troubles, the fiber density of the upper part 25 Is preferably lower.

Although the value of the fiber density in the recessed part 22 and the fiber density in the bottom part 24 of the convex part 23 is based also on the specific use of the surface sheet 10, it is generally 0.01-0.08 g / cm < ³ >, Especially 0.015- If it is 0.06 g / cm < ³ >, the advantageous effect mentioned above will be show | played effectively. Moreover, it is preferable that the fiber density in the upper part 25 of the convex part 23 is 0.01-0.07 g / cm < ³ >, especially 0.01-0.05 g / cm < ³ >.

  The measurement method of the fiber density in the recessed part 22 and the fiber density in the bottom part 24 and the upper part 25 of the convex part 23 is as follows. The volume of the convex part 23, the concave part 22, and the groove part 30 of the surface sheet 10 for which the weight ε, the length and the width are measured is measured and calculated as follows, and the average fiber density of the entire surface sheet is obtained, and the fiber density of each part Is calculated. Specifically, first, the aperture area of the aperture 31 and the plane (upper surface) area of the convex portion 23 are measured by an image analysis device. The surface sheet itself can be used for the measurement, but an enlarged photograph in which the opening 31, the convex portion 23, and the concave portion 22 are marked can also be used. First, the average plane area of the opening 31, the convex part 23, and the concave part 22 is measured from 50 to 100 accumulated numbers for each part. By multiplying each measured average plane area by the number of apertures 31, convex portions 23, and concave portions 22 (values to the first decimal place), the apertures 31, convex portions 23, and concave portions 22 of the surface sheet 10 are obtained. A plane area is calculated. And the plane area of a groove part is calculated by subtracting the sum total of each of these plane areas from the apparent area of a surface sheet. Next, in order to calculate the volume V1 of the upper part 25 of the convex part 23, the volume V2 of the bottom part 24 of the convex part 23, the volume V3 of the concave part 22, and the volume V4 of the groove part 30 excluding the opening 31, The longitudinal length L1 of the convex portion 23 and the longitudinal length L3 of the concave portion 22 are measured. And the cross-sectional area Sn of each site | part is measured from a cross-sectional photograph with an image analyzer. Here, n is an integer, the upper portion 25 of the convex portion 23 is 1, the bottom 24 of the convex portion 23 is 2, the concave portion 22 is 3, and the groove portion 30 is 4. The volume Vn of each part can be calculated by multiplying the length in the longitudinal direction and the cross-sectional area. Regarding the volume V1 of the upper portion 25 of the convex portion 23, it is necessary to correct the volume by a three-dimensional shape, and the shape that can be formed by cutting in half at the center in the longitudinal direction and overlapping the surfaces on the bottom portion 24 side is a cylinder / cone -The volume is calculated by judging whether the shape of a truncated cone, a combination of a hemisphere and a truncated cone (or a polygonal cylinder) is close.

The average fiber density [rho _M of the topsheet is sought from _{ρ M = ε / (V1 +} V2 + V3 + V4), the fiber density .rho.n is in each site can be calculated from ρn = kn · ρ _M. Here, kn is a fiber density coefficient obtained from kn = (Δ1 + Δ2 + Δ3 + Δ4) / 4Δn. The fiber density coefficient kn is a cross-sectional photograph (300 to 500 times by an electron microscope or the like, which is substantially orthogonal to the fiber orientation in the upper portion 25, the bottom portion 24, the concave portion 22 and the groove portion 30 of the convex portion 23, and the bottom portion 24 and the upper portion 25 are the same photograph. It is preferable that the space area Δn formed by 10 fibers from 10 sheets each (the centers of the fibers can be connected so that the distance between the fibers is the shortest, and as many fibers as possible can be connected by a line) Measure and calculate. For each unit, the weight ε is g, Sn and Δn are cm ² , Vn is cm ³ , and ρ _M and ρn are g / cm ³ . Further, even if the longitudinal length L3 of the recess 22 is 0, ρ3 is calculated.

  As shown in FIGS. 1A and 1C, a large number of apertures 31 are formed in the groove 30. The opening 31 is formed by separating the constituent fibers of the topsheet 10. The openings 31 are regularly and intermittently formed at regular intervals along the longitudinal direction of the groove 30. Therefore, the top sheet 10 is formed in a state in which a plurality of aperture rows made of a large number of apertures 31 arranged at regular intervals along the Y direction are formed in multiple rows over the X direction of the top sheet 10. It has become. The pitch of the arrangement of the apertures 31 in all aperture rows is the same. In two adjacent rows of apertures, the apertures 31 are located at the same position in the X direction of the topsheet 10. And when the sheet | seat whole region is seen along the X direction of the surface sheet 10, this hole 31 is arrange | positioned so that the site | part in which the hole 31 is not necessarily formed exists. Further, when viewed from the entire surface sheet 10, the apertures 31 are distributed and arranged so as to form a multi-row row in the X direction of the sheet 10 and a multi-row row also in the Y direction. By arranging the apertures 31 in this way, the apertures 31 can be formed more efficiently by dividing the fibers than when the apertures 31 are arranged in a staggered pattern, for example. Can do.

The opening 31 can take various shapes in a plan view of the topsheet 10. For example, a shape such as a circle, an oval, an ellipse, a triangle, a quadrangle, a hexagon, or a combination thereof can be given. What is necessary is just to determine the shape and magnitude | size of the opening 31 suitably according to the specific use of the surface sheet 10. FIG. As an example, the size of the opening 31 is approximately 0.5 to ⁵ mm ² in terms of a projected area of the top sheet 10 in plan view, from the viewpoint of liquid permeability and maintaining the strength of the top sheet 10. preferable. The size of the opening 31 is measured using an image analysis system. Specifically, a light source [Sunlight SL-230K2; manufactured by LPL Co., Ltd.], stand [copy stand CS-5; manufactured by LPL Co., Ltd.], lens [24 mm / F2.8D Nikkor lens], CCD camera [(HV-37; manufactured by Hitachi Electronics Co., Ltd.) F lens mount connection] and video board [Spectra 3200; manufactured by Canopus Co., Ltd.], the second surface 10b side of the topsheet 10 Import the images. The captured image is binarized by the image analysis software NEW QUABE (ver. 4.20) manufactured by NEXTUS. The average value of the individual areas obtained from the binarized image is taken as the size of the aperture.

  The opening 31 may have an end projecting toward the second surface 10b of the topsheet 10 to form a liquid introduction pipe including the projecting portion. By forming such a protrusion, the cushioning property of the topsheet 10 is further enhanced. Moreover, since the contact between the topsheet 10 and the absorber can be maintained regardless of the structure of the absorber located on the lower side of the topsheet 10 by forming the protruding portion, the liquid excreted from the wearer is It is efficiently transmitted from the top sheet 10 to the absorber.

  With respect to the positional relationship between the opening 31 and the recess 22 formed in the flange 20 described above, as shown in FIG. 1A, the position is between the adjacent recesses 22 and 22 in the extending direction Y of the flange 20. Adjacent to each other, an opening 31 is formed in the groove 30. In other words, when viewed along the X direction of the topsheet 10, the recess 22 is positioned between the front and rear adjacent openings 31 in the direction Y in which the groove 30 extends. Therefore, when viewed along the X direction of the topsheet 10, the opening 31 is adjacent to the portion where the recess 22 is not formed in the flange portion 20, and the portion where the opening 31 is not formed in the groove portion 30. , Adjacent to the recess 22 of the flange 20. Since the opening 31 and the recess 22 have such a positional relationship, according to the napkin 1 of the present embodiment, the recess 22 and the non-opening portion of the groove 30 are adjacent to each other in the X direction of the topsheet 10. Will fit. As a result, the convex portion 23 and the opening 31 are adjacent to each other, thereby providing an advantageous effect that the opening 31 is prevented from coming into direct contact with the wearer's skin.

In the surface sheet 10, the substantial basis weight differs between the convex portion 23 of the flange portion 20 and the groove portion 30 (excluding the opening 31). In other words, the amount of fibers is different between the convex portion 23 and the groove portion 30. Specifically, the amount of fibers is substantially larger in the convex portion 23 than in the groove portion 30. The amount of fibers is the amount of fibers present per unit area when the topsheet 10 is viewed in plan. Since the convex part 23 and the groove part 30 are formed in this way, the convex part 23 can be deformed flexibly while being hardly crushed. If the fiber weight of the convex part 23 and the groove part 30 is represented by basic weight, it is preferable that the basic weight of the convex part 23 is 30-150 g / m < ² >, especially 40-100 g / m < ² >. On the other hand, it is preferable that the basic weight of the groove part 30 is 10-70 g / m < ² >, especially 15-50 g / m < ² >. The basis weight as a whole of the top sheet 10 (including the recess 22 and the opening 31) is preferably 20 to 80 g / m ² , particularly 30 to 80 g / m ² from the viewpoints of flexibility and nonwoven fabric strength. The basis weight of the convex part 23 is the weight ρ1 · V1 of the top part of the convex part and the weight ρ2 · V2 of the bottom part of the convex part in the surface sheet in which the weight ε, the length and the width are measured from the respective volumes and fiber densities described above. Is calculated from (ρ1 · V1 + ρ2 · V2) / S1 (where S1 represents the plane (upper surface) area of the convex portion 23).

  As the fibers constituting the top sheet 10, fibers conventionally used in the technical field such as natural fibers, semi-natural fibers, and synthetic fibers can be used without particular limitation. From the viewpoint of imparting flexibility to the topsheet 10 without causing clogging between fibers, it is preferable to use synthetic fibers. The blending amount of the synthetic fiber is preferably 50% by weight or more, more preferably 70% by weight or more of the entire surface sheet. Of course, you may comprise the surface sheet 10 from 100% of synthetic fiber. When the topsheet 10 is made of 100% synthetic fiber, the ridge groove structure is not easily crushed even when the wearer's body pressure is applied, and thus the air permeability in the planar direction on the first surface 10a side of the topsheet 10 is good. It becomes.

  Examples of the synthetic fiber used include core-sheath fibers and side-by-side fibers that are self-bonding fibers. In addition, single fibers and composite fibers such as polyethylene, polypropylene, and polyester can be used. From the viewpoint of improving the flexibility by forming a groove structure and an opening shape, and by forming a bridging bond shape, it is possible to use a core-sheath fiber having polyethylene as a sheath component or a side-by-side fiber having a polyethylene portion. preferable. The (average) fineness of the fiber is preferably in the range of 1 to 6 dtex.

  It is preferable to use crimped fibers as the synthetic fibers because the cushioning property of the topsheet 10 is further improved. As the crimped fiber, either a two-dimensionally crimped fiber or a coiled three-dimensionally crimped fiber can be used. In particular, it is preferable that the surface sheet 10 includes fibers that are three-dimensionally crimped in a coil shape by application of heat. Such a fiber can be included in the topsheet 10 by using latent crimped fibers as a raw material. The latent crimped fiber is composed of, for example, an eccentric core-sheath type composite fiber or a side-by-side type composite fiber containing two types of thermoplastic resins having different shrinkage rates as components. Examples thereof include those described in JP-A-9-296325 and Japanese Patent No. 2759331.

  Even if a fiber that elongates by application of heat is used as the synthetic fiber, the cushioning property of the topsheet 10 is further enhanced, which is preferable. This is because clogging between fibers due to heat applied during the manufacture of the topsheet 10 is prevented. As such a fiber, for example, WO2007 / 66599 according to the previous application of the present applicant can be mentioned.

  When any of the above-described crimped fibers and heat-extensible fibers is used, it is preferable that those fibers are mixed in the surface sheet 10 in a total amount of 30 to 70% by weight.

  The constituent fibers of the top sheet 10 are not particularly limited in the fiber length, and any of staple fibers and continuous filaments can be used depending on the method for producing the top sheet 10. When two or more kinds of fibers are used, the fiber lengths of these fibers may be the same or different.

  The top sheet 10 is preferably made hydrophilic. Examples of the hydrophilization method include a method of treating a hydrophobic non-woven fabric with a hydrophilizing agent. Moreover, the method of manufacturing a nonwoven fabric from the fiber which knead | mixed the hydrophilizing agent is mentioned. Further, there is a method of using a fiber having hydrophilicity inherently, for example, a natural or semi-natural fiber. Hydrophilicity can also be achieved by applying a surfactant after the production of the nonwoven fabric.

  Although the surface sheet 10 shown in FIGS. 1A to 1C has a single-layer structure, the surface sheet 10 can be replaced with a multilayer structure having two or more layers. When the topsheet 10 has a two-layer structure including, for example, an upper layer including the first surface 10a and a lower layer including the second surface 10b, it is preferable to increase the capillary gradient of the lower layer as compared to the upper layer. Thereby, the drawability of the liquid from the first surface 10a side to the second surface 10b side is promoted. As a method of increasing the capillary gradient, for example, a method of reducing the fiber diameter of the lower layer fibers than the upper layer can be mentioned. In this case, it is preferable that the upper fiber is 2 to 8 dtex and the lower fiber is 0.1 to 6 dtex. Also, the capillary gradient can be increased by increasing the hydrophilicity of the lower layer than the upper layer. Or you may employ | adopt both these means.

  Next, the suitable manufacturing method of the surface sheet 10 of this embodiment is demonstrated. FIG. 2 schematically shows an example of an apparatus suitably used for manufacturing the top sheet 10. The apparatus 100 shown in FIG. 2 includes a three-dimensional shaping unit 120, a fluid blowing unit 130, and a hot air blowing unit 140.

  The three-dimensional shaping part 120 is a cylindrical thing, and rotates in the direction shown by the arrow in FIG. A cavity (not shown) is provided inside the three-dimensional shaped portion 120, and the cavity is connected to a suction device (not shown). By operating the suction device, the three-dimensional shaped portion 120 can suck the fluid from the outside toward the inside through the peripheral surface. The three-dimensional shaping part 120 is provided with a three-dimensional shaping member 121 on its peripheral surface. Details of the three-dimensional shaping member 121 will be described later. The fluid blowing unit 130 includes a fluid blowing nozzle. The nozzle has a structure capable of spraying fluid over the entire area of the three-dimensional shaped portion 120 in the axial direction. The types of fluid that can be used in this embodiment will be described later. The hot air blowing unit 140 includes a hot air blowing nozzle. The nozzle has a structure capable of blowing hot air over the entire area of the three-dimensional shaped portion 120 in the axial direction. In FIG. 2, the fluid blowing unit 130 and the hot air blowing unit 140 are each represented by a single-stage nozzle. However, the fluid blowing unit 130 and / or the hot air blowing unit 140 are used as necessary. May be configured with multi-stage nozzles installed along the rotation direction of the three-dimensional shaped portion 120.

  3 and 4 are a perspective view and a plan view of the three-dimensional shaped member 121 in the three-dimensional shaped portion 120. FIG. 3 and 4 show the three-dimensional shaping member 121 shown in FIG. The three-dimensional shaping member 121 includes a corrugated sheet-like support body 122. The support body 122 has a wave shape in the direction indicated by the symbol X in FIG. 3, and ridges and recesses are alternately arranged along the Y direction, which is a direction orthogonal to the X direction. The ridges and ridges extend in the X direction. The Y direction coincides with the circumferential direction in the three-dimensional shaped portion 120, that is, the rotation direction. The support body 122 has a mesh structure (net) in a direction Y orthogonal to the corrugated direction X. However, the shape of the support body 122 is not limited to this. For example, the support body 122 may be connected with a rod-shaped object in the X and Y directions, or a hole may be provided in an elongated flat plate-shaped object. In other words, the support body 122 only needs to have an uneven shape extending in one direction. The support 120 has a ring shape having the same curvature as that of the peripheral surface of the three-dimensional shaped portion 120. Each support body 122 is arrange | positioned so that it may be located on the same surrounding surface at equal intervals.

The area of each mesh of the support 122 is 1.8 to 30.0 mm ² , particularly 3.0 to 25.0 mm, from the viewpoint of giving sufficient strength to the three-dimensional shaping member 121 and preventing the fibers from being entangled. ² is preferred.

  As shown in FIG. 3, the three-dimensional shaping member 121 includes a plurality of plate-like convex portions 123 formed on the tops of the ridges of the support body 122 in addition to the support bodies 122 and a connecting portion 128 disposed on the ridges. ing. The plate-like convex portions 123 are arranged at a predetermined interval in the same direction as the direction in which the ridges extend. The connecting part 125 is a plate-like body having substantially the same shape as the cross-sectional shape of the concave stripe, and is arranged in a row in the X direction in the figure. Each plate-like convex part 123 is the same shape. The same applies to the connecting portion 128. The plate-like convex portion 123 has a plate-like shape having two parallel wide surface portions 124 facing each other. The wide surface portion 124 is orthogonal to the direction X in which the support body 122 extends. That is, the plate-like convex portion 123 is disposed so as to have the wide surface portion 124 orthogonal to the direction X in which the support body 122 extends. Further, the plate-like convex portion 123 gradually decreases in width as it goes from the lower end to the upper end. The plate-like convex portion 123 has an isosceles triangular shape that has a rounded tip and an oblique side that is convex toward the outside. The plate-like convex portion 123 is coupled to the support body 122 at the lower end thereof. Moreover, the connection part 128 is formed in the substantially same height as the top part of a protruding item | line. In the present embodiment, each plate-like convex portion 123 and connecting portion 128 are all the same shape, but instead of this, plate-like convex portions and connecting portions 128 having different shapes (for example, different heights) may be used in combination. Good.

  As shown in FIG. 4, the plurality of plate-like convex portions 123 are arranged in series along the direction Y with the wide surface portion 124 oriented in the direction Y orthogonal to the direction X in which the support body 122 extends. A subgroup row 125 is formed. The plate-like convex portion group rows 125 are arranged in multiple rows along the direction X in which the support body 122 extends. The interval between the plate-like convex group groups 125 adjacent in the X direction is equal pitch P2. Further, the connecting portion 128 has a convex curved surface in which the opposing plate surface portions gently bulge outward.

  The pitch P2 between the plate-like convex group groups 125 moving back and forth along the extending direction X of the support 122 affects the bulkiness and texture of the three-dimensionally shaped nonwoven fabric obtained according to the present manufacturing method. From the viewpoint of obtaining a non-woven fabric that is bulky and has a good texture, the pitch between the front and rear plate-like convex group groups 125 is preferably 2.0 to 20.0 mm, particularly preferably 5.0 to 15.0 mm. Moreover, since the height of the connection member 12 affects the ease of bending of the support body 122, it is preferable that the height of the connection member 12 is set to 50 to 100% of the depth of the groove.

  As shown in FIG. 4, in the three-dimensional shaping member 121, a rectangular shape is surrounded by the support body 122, two plate-like convex portions 123 adjacent in the front-rear direction with respect to the X direction, and a connecting portion 128 adjacent in the left-right direction with respect to the Y direction. An opening 126 is formed. The plurality of openings 126 are arranged in series at equal intervals along the direction X in which the support 122 extends. The opening rows are arranged in multiple rows along a direction Y orthogonal to the direction X in which the support body 122 extends. Thereby, when it sees in the three-dimensional shaping member 121 whole, the opening part 126 is arrange | positioned at the grid | lattice form. Each opening 126 communicates with a cavity provided inside the three-dimensional shaped portion 120 described above. Since this cavity is connected to the suction device as described above, when the suction device is operated, fluid is sucked from the outside to the inside of the three-dimensional shaped portion 120 through the opening 126.

The magnitude | size of each opening part 126 affects the bulkiness of the surface sheet 10 obtained according to this manufacturing method. From the viewpoint of obtaining a bulky surface sheet 10, the area of the opening 126 is preferably ² to 170 mm ² , particularly 10 to 170 mm ² in plan view.

  The three-dimensional shaping member 121 is made of a net-like molded body having appropriate holes made of resin or metal material, and the support body 122 and the plate-like convex portion 123 are integrated. Therefore, there is no gap for fibers to enter between the support body 122 and the plate-like convex portion 123 in the three-dimensional shaping member 121, and the net-like molded body is hardly entangled. As a result, when the surface sheet 10 obtained by three-dimensional shaping of the fiber web by the method described later using the three-dimensional shaping member 121 is removed from the three-dimensional shaping member 121, the operation can be smoothly performed. it can. This is advantageous from the viewpoint of continuous production of the topsheet 10. This is because the manufacturing apparatus 100 may have to be stopped if the surface sheet 10 is not removed successfully. Smooth removal of the topsheet 10 is advantageous from the point that it is difficult for the topsheet 10 that has been removed to fluff.

  The height H (see FIG. 3) of the plate-like convex portion 123 affects the bulkiness of the topsheet 10 obtained according to the present manufacturing method from the viewpoint of suitability or separation from the support 122. From the viewpoint of obtaining the bulky surface sheet 10, the height H of the plate-like convex portion 123 is preferably 2 to 30 mm, and particularly preferably 5 to 10 mm. Similarly, the width W (see FIG. 4) of the plate-like convex portion 123 also affects the bulkiness of the topsheet 10 cloth. From this viewpoint, the width W of the plate-like convex portion 123 is preferably 1 to 20 mm, particularly 2 to 10 mm. Since the plate-like convex portion 123 is coupled to the top of the ridge as described above, the width W of the plate-like convex portion 123 substantially coincides with the pitch between the adjacent support bodies 122. .

  The three-dimensional shaping member 121 is preferably made of a resin or a metal material from the viewpoint of integral molding of the support body 122 and the plate-like convex portion 123. Resins that can be used include various thermoplastic resins such as polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyamide resins such as polyamide 6 and polyamide 66, and vinyl such as polystyrene. Resin, polyacetal resin, acrylic resin and the like. If the three-dimensional shaped member 21 is required to be elastic, a thermoplastic elastomer can be used. Moreover, a thermosetting resin can also be used depending on the method of resin molding. In addition, when durability is requested | required of the three-dimensional shaping member 121, it may replace with resin and may use a metal material. In the case of using a metal material, the three-dimensional shaped member 121 can be manufactured by casting or shaving, for example.

  The manufacturing method of the topsheet 10 using the apparatus 100 having the three-dimensionally shaped portion 120 including the three-dimensionally shaped member 121 having the above configuration will be described with reference to FIG. The fiber web 10 ′ is manufactured using the material as a raw material. The fiber web 10 'is manufactured, for example, by opening a fiber material as a raw material with a card machine. The basis weight of the fiber web 10 ′ is the same as the basis weight of the target topsheet 10. Therefore, an appropriate value is selected as the basis weight of the fiber web 10 ′ according to the specific application of the target topsheet 10.

  The manufactured fiber web 10 ′ is introduced into the top sheet 10 manufacturing apparatus 100 via the guide roll 101 as shown in FIG. 2. The fiber web 10 ′ introduced into the apparatus 100 is disposed on the peripheral surface of the three-dimensional shaped portion 120 that rotates in the direction indicated by the arrow in the drawing. This state is shown in FIG. At this time, as shown in FIG. 5A, the fiber web 10 ′ is in a state of being placed on the three-dimensional shaping member 121 of the three-dimensional shaping portion 120.

  The fiber web 10 ′ is conveyed in a state of being placed on the three-dimensional shaping member 121 and reaches the position of the fluid blowing portion 130 shown in FIG. 2. The fluid blown from the fluid blowing portion 130 is blown onto the fiber web 10 ′ facing the fluid blowing portion 130. The sprayed fluid is sucked from the surface opposite to the spray surface. That is, the fluid is sucked from the outside to the inside of the three-dimensional shaped portion 120 through the opening 126 (see FIG. 4) formed in the three-dimensional shaped member 121 by the operation of a suction device (not shown). Due to the spray pressure of the fluid, the constituent fibers of the fiber web 10 ′ sink between the plate-like convex portions 123 in the three-dimensional shaping member 121 as shown in FIG. Further, among the constituent fibers of the fiber web 10 ′, the fibers positioned on the plate-like convex portion 123 of the three-dimensional shaping member 121 are separated by the plate-like convex portion 123.

  The fiber web 10 ′ changes from the state shown in FIG. 5 (b) to the state shown in FIG. 5 (c) depending on the spray pressure of the fluid from the fluid blowing part 130 and the type of fluid. In the fiber web 10 ′ in the state shown in FIG. 5C, the constituent fibers located between the plate-like convex portions 123 are greatly sinked between the plate-like convex portions 123. Thereby, the convex part 23 in the target surface sheet is formed. This sinking is regulated by the support 122. Due to this restriction, the recess 22 is formed. In addition, among the constituent fibers of the fiber web 10 ′, the fibers positioned on the plate-like convex portion 123 of the three-dimensional shaping member 121 further advance the fiber by the plate-like convex portion 123. Thereby, the opening 31 in the target surface sheet is formed. By appropriately controlling the degree of sinking of the web 10 ′, the fiber density in the concave portion 22 and the fiber density in the bottom portion 24 of the convex portion 23 can be made substantially equal.

  As the fluid blown out from the fluid blowing portion 130, for example, air, water vapor, water, or the like can be appropriately selected and used according to the degree of uneven forming on the fiber web 10 '. When air is used, it may be used without being heated or may be used after being heated. When using heated air, it is heated below the fusing start temperature of the heat-fusible fiber contained in the fiber web 10 '. Whether air is heated or not, when air is used as the fluid, the spraying condition is preferably 10 m / sec or more, and more preferably 20 to 60 m / sec.

  When water vapor is used as the fluid, the temperature is set to be equal to or lower than the fusion start temperature of the heat-fusible fiber contained in the fiber web 10 '. Moreover, it is preferable that the temperature of the atmosphere of the manufacturing apparatus 100 is higher than the dew point from the viewpoint of preventing water vapor from condensing during the spraying onto the fiber web 10 '. The conditions for spraying water vapor are preferably a vapor pressure of 0.3 to 0.8 MPa and a vapor temperature of 140 to 200 ° C.

When water is used as the fluid, the spraying conditions are preferably a pressure of 5 to 50 kg / cm ² and a flow rate of 1 to 20 l / m ² .

  Returning to FIG. 2, the fiber web 10 ′ that has passed through the position facing the fluid blowing portion 130 is inserted between the push roll 102 and the three-dimensional shaping member 121 arranged to face the three-dimensional shaping member 121. Is done. The peripheral surface of the push roll 102 is smooth. The peripheral surface of the pushing roll 102 is made of, for example, a metal material or a rubber material. In the fiber web 10 ′ inserted between the push roll 102 and the three-dimensional shaping member 121, the constituent fibers further sink between the plate-like convex portions 123 by the push of the push roll 102. Further, among the constituent fibers of the fiber web 10 ′, those positioned on the plate-like convex portion 123 of the three-dimensional shaping member 121 are further separated by the plate-like convex portion 123.

  The fiber web 10 ′ that has passed between the push roll 102 and the three-dimensional shaping member 121 is further conveyed and reaches the position of the hot air blowing section 140 shown in FIG. 2. Hot air blown from the hot air blowing portion 140 is blown onto the fiber web 10 ′ facing the hot air blowing portion 140. The hot air blown is sucked from the surface opposite to the spray surface. By this operation, the heat-fusible fibers contained in the three-dimensionally shaped fiber web 10 'are fused at their intersections, and the fiber web 10' is made into a nonwoven fabric. Thereby, the target surface sheet 10 is obtained.

  As the temperature of the hot air to be blown, an appropriate value is selected according to the fusing start temperature of the heat-fusible fiber contained in the fiber web 10 '. In general, it is possible to maintain the fiber structure of the heat-fusible fiber by using hot air having a temperature that is higher than the fusing start temperature T of the heat-fusible fiber and T + 30 ° C. or less, particularly T + 5 ° C. or more and T + 20 ° C. or less. However, it is preferable from the viewpoint of reliably performing the fusion.

  Thus, the target surface sheet 10 is obtained. In the obtained surface sheet 10, uneven three-dimensional shapes and openings are given to the surface facing the three-dimensional shaping member 121. The convex portions are formed from the fibers that sink between the plate-like convex portions 123 of the three-dimensional shaping member 121. The concave portion is formed due to the regulation of the sinking of the fiber by the support body 122. The opening is formed due to the separation of fibers located on the plate-like convex portion 123.

  The obtained topsheet 10 is removed from the three-dimensional shaping member 121 by the peeling roll 103 in the apparatus 100. In this case, as described above, there is no gap for fibers to enter between the support 122 and the plate-like convex portion 123 in the three-dimensional shaped member 121, so that the three-dimensional shaped nonwoven fabric 1 can be removed smoothly. It is carried out and it is difficult for the surface sheet 10 to fluff.

  Thus, the target nonwoven fabric (surface sheet) is obtained. This top sheet is typically used together with a liquid-impermeable or water-repellent back sheet, and an absorbent article is formed by sandwiching a liquid-retaining absorbent between the two sheets. Examples of such absorbent articles include various products known in the art such as sanitary napkins and disposable diapers. Moreover, the nonwoven fabric manufactured by the above-mentioned method can be used also for uses other than the surface sheet of an absorbent article. Examples of such applications include cleaning sheets.

  Next, second to fourth embodiments of the present invention will be described with reference to FIGS. Regarding the second to fourth embodiments, points different from the first embodiment described above will be described, and for the points not particularly described, the description regarding the above-described embodiments will be applied as appropriate. 6 to 10, the same members as those in FIGS. 1 to 5 are denoted by the same reference numerals.

  The topsheet 10 of the second embodiment shown in FIGS. 6A to 6C is different from the first embodiment in the shape of the recess 22 in the flange portion 20. Specifically, in the first embodiment, the height of the concave portion 22 and the height of the groove portion 30 were approximately equal, but in this embodiment, the concave portion 22 is more as apparent from FIG. 6B. It is higher than the groove 30.

  In the present embodiment, as in the first embodiment, the fiber amount of the flange portion 20 is larger than the fiber amount of the groove portion 30, and in addition to this, when paying attention only to the flange portion 20, The fiber amount of the convex portion 23 is larger than the fiber amount of the concave portion 22. Therefore, when comparing the entire flange portion 20 and the groove portion 30, (a) the fiber amount at the convex portion 23, (b) the fiber amount at the concave portion 22, and (c) the groove portion 30 (excluding the opening 31). The amount of fibers decreases in the order of (A)> (B)> (C). By controlling the amount of fibers in this manner, there is an advantage that when the topsheet 10 is bent with the recess rows 22A as the flexible shaft, wrinkles are less likely to occur at the bent portion.

  The topsheet 10 of this embodiment can be manufactured using the apparatus (refer FIGS. 2-4) used for manufacture of the topsheet 10 of 1st Embodiment. In this case, the surface sheet 10 shown in FIGS. 6A to 6C can be successfully manufactured by appropriately adjusting the type of fluid and the spray pressure of the fluid by the fluid blowing portion 130 (see FIG. 2). it can. In this case, in order to reduce the fiber amount at the convex portion 23, the fiber amount at the concave portion 22, and the fiber amount at the groove portion 30 in this order, the manufacturing process of the topsheet 10 using the apparatus 100 shown in FIG. In this case, the degree of fluid spraying using the fluid blowing portion 130 may be appropriately adjusted.

  In the topsheet 10 of the third embodiment shown in FIGS. 7A to 7C, each flange 20 extends in one direction (in the Y direction in FIG. 7A) in a zigzag shape (triangular wave shape). Yes. The concave portion 22 of the flange portion 20 is located at the bending point of the zigzag. And the site | parts other than the bending point of a zigzag are comprised from the convex part 23. FIG. Since each collar part 20 is zigzag-shaped, the groove part 30 located between the collar parts 20 is also zigzag-shaped. The zigzag (triangular wave) amplitude and period in each collar 20 are the same. Furthermore, the phase is also the same. Since the flange part 20 and the groove part 30 are configured as described above, the diffusion of the liquid along the extending direction of the flange part 20 and the groove part 30 (the Y direction in FIG. 7A) is reduced. Since the groove part 30 is easily disturbed as compared with the case where the groove part 30 is linear, the liquid permeability in the thickness direction of the topsheet 10 is preferentially generated. As a result, liquid flow on the surface of the top sheet 10 is difficult to occur, and liquid leakage is less likely to occur. Moreover, the compression resistance of the convex part 23 in the collar part 20 becomes high, and when the pressure is applied, the convex part 23 is not easily crushed or collapsed. In addition, the form stability of the top sheet 10 on the first surface 10a side is increased.

  From the viewpoint of making the above-described effect more prominent, the zigzag period in each collar 20 is preferably 10 to 50 mm, particularly preferably 15 to 30 mm, and the amplitude is 3 to 30 mm, particularly 5 to 15 mm. preferable.

  As in the second embodiment shown in FIGS. 6A to 6C, the surface sheet 10 of the present embodiment has a height higher than the groove portion 30 in the recessed portion 22 of the flange portion 20. . However, the second embodiment is different from the second embodiment in that the concave portion 22 is a mountain shape having a single vertex in the cross-sectional shape in the X direction. In the present embodiment, similarly to the second embodiment, when attention is paid to the collar portion 20, the fiber amount of the convex portion 23 is larger than the fiber amount of the concave portion 22. Therefore, when comparing the entire flange portion 20 and the groove portion 30, (a) the fiber amount at the bottom 24 of the convex portion 23, (b) the fiber amount at the concave portion 22, and (c) the groove portion 30 (excluding the opening 31). ) In the order of (A)> (B)> (C). As a result, as in the second embodiment, when the topsheet 10 is bent with the recess rows 22A as the flexible shaft, there is an advantage that wrinkles are less likely to occur at the bent portion.

  Moreover, the surface sheet 10 of this embodiment forms the opening 31 in the groove part 30 adjacent to the position between the recessed parts 22 adjacent in the direction where the collar part 20 is extended similarly to the 1st and 2nd embodiment. Has been. As a result, the same effects as the effects exhibited in the first and second embodiments are exhibited.

  The topsheet 10 of this embodiment can be manufactured using the apparatus (refer FIGS. 2-4) used for manufacture of the topsheet 10 of the 1st and 2nd embodiment. However, as the three-dimensional shaping member 121 in the three-dimensional shaping portion 120, the one in which the plate-like convex portions 123 are arranged as shown in FIG. 8 is used. In the three-dimensional shaping member 121 shown in the figure, the plate-like convex portion 123 has a wide surface portion 124 in a direction that intersects the extending direction X of the support body 121 at an angle smaller than 90 degrees. The intersection angle θ is preferably 45 degrees or more and less than 90 degrees.

  In the top sheet 10 of the fourth embodiment shown in FIGS. 9A to 9C, each flange 20 has a zigzag shape (like the third embodiment shown in FIGS. 7A to 7C). It extends in one direction (triangular wave shape) in one direction (Y direction in FIG. 9A). Further, the zigzag (triangular wave) has the same amplitude and cycle in each collar 20 as in the third embodiment. However, this embodiment is different from the third embodiment in that the phase of the zigzag (triangular wave) in each flange 20 is shifted. Specifically, the phase of the zigzag (triangular wave) is shifted by ½ wavelength in the adjacent flanges 20.

  While the flange portion 20 has a zigzag shape as described above, the groove portion 30 does not have a zigzag shape. As shown in FIG. 9A, the groove portion 30 has a shape in which rhombus-shaped portions 30a surrounded by four convex portions 23 are arranged in series and connected in the Y direction. And the opening 31 is formed in the center of each site | part 30a. Therefore, in the surface sheet 10 of this embodiment, the opening 31 is formed in the groove part 30 adjacent to the recessed part 22 in the collar part 20. FIG. As a result, when the topsheet 10 is bent with the recess row 22A as the flexible shaft, the flexible shaft is divided at the opening 31. There is an advantage that does not become continuous.

  The topsheet 10 of this embodiment can be manufactured using the apparatus (refer FIGS. 2-4) used for manufacture of the topsheet 10 of the 1st thru | or 3rd embodiment. However, the thing shown in FIG. 10 is used as the three-dimensional shaping member 121 in the three-dimensional shaping part 120. In the three-dimensional shaped member 121 shown in these drawings, unlike the three-dimensional shaped member used in the previous embodiments, a quadrangular pyramid-shaped convex portion 127 is used instead of the plate-shaped convex portion. The quadrangular pyramid-shaped convex portion 127 has a rhombus bottom surface, and is arranged so that the diagonal of the short axis of the rhombus faces the X direction and the diagonal of the long axis faces the Y direction. A plurality of quadrangular pyramidal protrusions 127 are linearly arranged so as to contact the ends of the diagonals of the long axis in the rhombus portion on the bottom surface along the direction Y orthogonal to the direction X in which the support 122 extends. Yes. In the plan view of the entire three-dimensional shaped member 121, a plurality of quadrangular pyramidal convex portions 127 are arranged in a staggered pattern.

  In the support body 122, a concave line is formed along the direction Y at a portion where the quadrangular pyramidal convex portion 127 is not located. The X-direction length W2 of the quadrangular pyramid-shaped convex portion 127 and the X-direction length W1 of the adjacent adjacent stripes are such that W1 is 0.5 or less of W2, preferably -0.3 to 0.5. Since the web is difficult to contact the support 122, the recess 22 is easily formed in the obtained sheet without forming a recess. On the other hand, when W1 exceeds 0.5, preferably 0.5 to 1.2, the recess 22 is easily formed, so that a recess is formed. The depth of the recess is preferably 30 to 70% of W1.

  When the three-dimensional shaping member 121 shown in FIG. 10 is used, the opening 31 is formed at a portion corresponding to the quadrangular pyramidal convex portion 127. Further, the convex portion 23 is formed at a portion corresponding to the opening 126 surrounded by the four quadrangular pyramidal convex portions 127. Further, a concave portion 22 is formed between two quadrangular pyramidal convex portions 127 adjacent in the front-rear direction in the Y direction.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said form. For example, other embodiments may be configured by appropriately combining the above-described embodiments.

Fig.1 (a) is a principal part enlarged view in the planar view of 1st Embodiment of the nonwoven fabric of this invention, FIG.1 (b) and FIG.1 (c) are respectively b- in FIG.1 (a). It is b line sectional drawing and cc line sectional drawing. FIG. 2 is a schematic view showing an example of an apparatus suitably used for manufacturing the nonwoven fabric shown in FIG. FIG. 3 is a perspective view showing a three-dimensional shaping member in the three-dimensional shaping portion of the apparatus shown in FIG. FIG. 4 is a plan view showing a three-dimensional shaping member in the three-dimensional shaping unit of the apparatus shown in FIG. 5 (a) to 5 (c) are schematic views sequentially showing the production process of the nonwoven fabric using the apparatus shown in FIG. Fig.6 (a) is a principal part enlarged view in planar view of 2nd Embodiment of the nonwoven fabric of this invention, FIG.6 (b) and FIG.6 (c) are respectively b- in FIG.6 (a). It is b line sectional drawing and cc line sectional drawing. Fig.7 (a) is a principal part enlarged view in the planar view of 3rd Embodiment of the nonwoven fabric of this invention, FIG.7 (b) and FIG.7 (c) are respectively b- in FIG.7 (a). It is b line sectional drawing and cc line sectional drawing. FIG. 8 is a plan view (corresponding to FIG. 4) showing a three-dimensionally shaped member suitably used for manufacturing the nonwoven fabric shown in FIGS. 7 (a) to 7 (c). Fig.9 (a) is a principal part enlarged view in the planar view of 4th Embodiment of the nonwoven fabric of this invention, FIG.9 (b) and FIG.9 (c) are respectively b- in FIG.9 (a). It is b line sectional drawing and cc line sectional drawing. FIG. 10 is a perspective view (corresponding to FIG. 3) showing a three-dimensionally shaped member suitably used for manufacturing the nonwoven fabric shown in FIGS. 9 (a) to 9 (c).

Explanation of symbols

10 Nonwoven fabric (surface sheet)
20 ridge part 21 top part 22 concave part 23 convex part 24 bottom part of convex part 25 upper part of convex part 30 groove part 31 opening

Claims (6)

Projections of several formed are intermittently arranged in columns, and multiple ridges extending ridged in one direction, located between ridges adjacent and extending in the same direction as the ridges and a groove of several, a nonwoven fabric openings are formed in the groove,
Ridges is between convex portions adjacent to each other in the extending direction has a lower recess height than the convex portion, and in the ridges, and the fiber density in the concave portion, and the fiber density at the bottom of the convex portion has become equal properly,
A non-woven fabric in which the basis weight at the convex portion is greater than the basis weight at the groove (excluding apertures) . (B) a basis weight of the convex portion, in the order of a basis weight of at (b) a basis weight of at recess, and (iii) the groove (excluding opening) is, (a)>(b)> (c) The nonwoven fabric according to claim 1, wherein the nonwoven fabric is reduced.   The nonwoven fabric according to claim 1 or 2, wherein the collar portion extends in a zigzag shape, and the concave portion in the collar portion is located at a bending point of the zigzag. The nonwoven fabric according to claim 3, wherein an opening is formed in the groove portion adjacent to a position between adjacent concave portions in the extending direction of the flange portion. Projections of several formed are intermittently arranged in columns, and multiple ridges extending ridged in one direction, located between ridges adjacent and extending in the same direction as the ridges and a groove of several, a nonwoven fabric openings are formed in the groove,
The collar portion has a recess having a height lower than that of the protrusion between adjacent protrusions in the extending direction,
A non-woven fabric in which the heel portion extends in a zigzag shape and the recess is located at the bending point of the zigzag.   The nonwoven fabric according to claim 5, wherein an opening is formed in the groove portion adjacent to a position between adjacent recesses in the extending direction of the flange portion.

Images