JP6170822B2 - Nonwoven fabric and method for producing the same - Google Patents

Description

  The present invention relates to a nonwoven fabric containing long fibers and a method for producing the same.

  Conventionally, in the absorbent articles such as disposable diapers, perforated nonwoven fabrics having perforations are frequently used from the viewpoint of ensuring high air permeability. As a manufacturing method of an open-hole nonwoven fabric, for example, Patent Document 1 discloses a manufacturing method of a nonwoven fabric including a step of creating a plurality of openings by melting, and Patent Document 2 applies a high-pressure water stream. Discloses a method for producing a non-woven fabric comprising a step of further dividing fibers to form a plurality of openings.

  As another technique, the applicant firstly cut a part of the long fiber, fixes only one end by the heat-sealing part, and thickens the free end on the other end side. The nonwoven fabric provided with the fiber was proposed (refer patent document 3).

Japanese National Patent Publication No. 11-504684 JP 2000-265353 A JP2012-092475A

  However, the nonwoven fabric manufactured by the manufacturing method described in Patent Document 1 is a nonwoven fabric in which the melted portion becomes hard and the touch is inferior because the opening is formed by melting. In that respect, the nonwoven fabric manufactured by the manufacturing method described in Patent Document 2 is a nonwoven fabric having good touch and no hardened portions because the openings are formed by separating the fibers by applying a high-pressure water stream.

  However, since the nonwoven fabric manufactured by the manufacturing method described in Patent Document 2 has openings formed by dividing fibers by applying a high-pressure water stream in the vertical direction, the opening is formed in a plan view. A plurality of tracks are formed in a circular shape or a circular track shape such as a track in an athletic field. Such a circular or track circular opening is associated with a hole depending on the user and gives an image of poor quality of the nonwoven fabric. In addition, such a circular or track circular opening made it easy for the liquid once passed to wet back to the skin facing surface side through the opening.

  Patent Document 3 does not disclose any nonwoven fabric having an arc-shaped tearing portion that is torn in an arc shape, nor does it disclose any method for manufacturing a nonwoven fabric having the arc-shaped tearing portion.

  Therefore, this invention relates to providing the nonwoven fabric which can eliminate the said subject, and the manufacturing method of the nonwoven fabric.

  The present invention is a non-woven fabric formed from a web containing long fibers, and has a plurality of tearing parts formed by tearing the webs, and a part of the plurality of tearing parts is torn in an arc shape and The present invention provides a nonwoven fabric in which the outer peripheral edge of an arc-shaped tearing portion is rolled to form an opening.

Further, the present invention provides a nonwoven fabric manufacturing method in which a raw nonwoven fabric in which a web containing long fibers is fixed by a heat-sealing portion is supplied between a pair of concavo-convex rollers, and a plurality of portions of the nonwoven fabric are partially stretched. In the partial stretching process, the raw nonwoven fabric is stretched at a strain rate of 1 × 10 ² s ⁻¹ or more, and has a plurality of tear portions in which a web containing long fibers is torn. A part of the tear portion is provided with a non-woven fabric manufacturing method for manufacturing a non-woven fabric which is torn in an arc shape and an outer peripheral edge of the arc-shaped tear portion is rolled to form an opening.

According to the non-woven fabric of the present invention, high air permeability is ensured, the touch is good, and wet back (especially soft stool does not return to liquid) is difficult. Moreover, according to the nonwoven fabric of this invention, it is hard to associate a hole and the quality of the nonwoven fabric improves.
Moreover, according to the manufacturing method of the nonwoven fabric of this invention, such a nonwoven fabric can be manufactured continuously.

FIG. 1 is a plan view showing an embodiment of the nonwoven fabric of the present invention. FIG. 2 is an enlarged plan view of a main part of the nonwoven fabric shown in FIG. FIG. 3 is an explanatory diagram for explaining a method of measuring the breaking elongation in the X direction at one heat-sealed portion. FIG. 4 is an enlarged perspective view of a main part of the nonwoven fabric shown in FIG. FIG. 5 is a schematic view showing a method for measuring the amount of raised fibers of the nonwoven fabric of the present invention. FIG. 6 is a perspective view showing a fiber having a thick free end portion of the nonwoven fabric shown in FIG. FIG. 7 is a schematic view showing a preferred production apparatus used in the method for producing a nonwoven fabric of the present invention. FIG. 8 is a schematic diagram showing a partially stretched portion provided in the manufacturing apparatus shown in FIG. FIG. 9 is an enlarged cross-sectional view of a main part of the partially stretched portion shown in FIG. FIG. 10 is a schematic diagram illustrating a raised processing portion provided in the manufacturing apparatus illustrated in FIG. 7. FIG. 11 is a diagram for explaining an example of a usage pattern of the nonwoven fabric of the present invention, and is a developed plan view showing a state in which a pants-type disposable diaper is developed and extended. 12 is a cross-sectional view taken along the line II of FIG.

Hereinafter, the nonwoven fabric of this invention is demonstrated based on the preferable embodiment, referring FIGS.
As shown in FIG. 1, the nonwoven fabric 1 of the present embodiment is a nonwoven fabric formed from a web including long fibers 2, and has a plurality of tear portions 4 formed by tearing the web. For the nonwoven fabric 1, as shown in FIG. 1, the MD direction along the fiber orientation direction is determined as the longitudinal direction (Y direction) and the CD direction orthogonal to the MD direction along the fiber orientation direction is determined as the width direction (X direction). Therefore, in the following description, the Y direction and the MD direction mean the same direction, and the X direction and the CD direction mean the same direction.

  The non-woven fabric 1 of the present embodiment is a non-woven fabric formed by fixing a web containing long fibers 2 by a heat-sealing portion 3. More specifically, a web containing long fibers 2 is intermittently formed by a heat-sealing portion 3. In addition, it is formed on the basis of the nonwoven fabric 10 fixed by pressing or fusing each other's fibers. Hereinafter, this will be described as the original nonwoven fabric (raw material nonwoven fabric) 10. The raw material nonwoven fabric 10 is a nonwoven fabric before tearing the web containing the long fibers 2. Here, the “long fiber” has a fiber length of 30 mm or more, and the raw nonwoven fabric 10 is preferably a so-called continuous long fiber having a fiber length of 150 mm or more because a nonwoven fabric 1 having high breaking strength can be obtained. .

  The raw material nonwoven fabric 10 may be a nonwoven fabric formed from a web containing long fibers 2, but a nonwoven fabric formed by fixing a web containing long fibers 2 by the heat-sealing part 3 is preferable. Preferable specific examples of the raw material nonwoven fabric 10 formed by fixing the web containing the long fibers 2 by the heat-sealing part 3 include a spunbond nonwoven fabric, a laminated nonwoven fabric of a spunbond layer and a meltblown layer, or a card method. A heat roll nonwoven fabric etc. are mentioned. Examples of the laminated nonwoven fabric include spunbond-spunbond laminated nonwoven fabric, spunbond-spunbond-spunbond laminated nonwoven fabric, spunbond-meltblown-spunbond laminated nonwoven fabric, spunbond-spunbond-meltblown-spunbond laminated nonwoven fabric, etc. Can be mentioned.

  The long fibers 2 constituting the raw material nonwoven fabric 10 mainly contain a thermoplastic resin. Examples of the thermoplastic resin include polyolefin resins, polyester resins, polyamide resins, acrylonitrile resins, vinyl resins, vinylidene resins, and the like. Is mentioned. Examples of the polyolefin resin include polyethylene, polypropylene, and polybuden. Examples of the polyester resin include polyethylene terephthalate and polybutylene terephthalate. Nylon etc. are mentioned as a polyamide-type resin. Examples of the vinyl resin include polyvinyl chloride. Examples of the vinylidene resin include polyvinylidene chloride. One of these various resins can be used alone or in admixture of two or more, and modified products of these various resins can also be used. Moreover, a composite fiber can also be used as the long fiber 2 constituting the raw material nonwoven fabric 10. Side-by-side fibers, core-sheath fibers, core-sheath fibers having eccentric crimps, split fibers, and the like can be used as the composite fibers. When using a composite fiber, it is preferable to use a core-sheath fiber having a core made of polypropylene and a sheath made of polyethylene in that a soft nonwoven fabric 1 can be obtained. The fiber diameter of the long fibers 2 is preferably 5 μm or more and 30 μm or less, and more preferably 10 μm or more and 20 μm or less before processing described later.

  From the viewpoint of easily forming a first arc-shaped tearing portion 41 to be described later constituting the tearing portion 4 as the raw material nonwoven fabric 10, in the direction (X direction) orthogonal to the orientation direction of the long fibers 2 in one thermal fusion portion 3. It is preferable to use a nonwoven fabric having a breaking elongation of 45% or less, more preferably a nonwoven fabric of 35% or less, and particularly preferably a nonwoven fabric of 30% or less. In addition, it is preferable to use the nonwoven fabric whose lower limit of the said breaking elongation is 5% or more. The breaking elongation is measured by the following method.

[Measurement method of breaking elongation in X direction at one heat-sealed portion 3]
In a 22 ° C. and 65% RH environment, a rectangular measuring piece having a size of 10 mm or more in the orientation direction (Y direction) of the long fibers 2 and 50 mm or more in the direction orthogonal to the orientation direction (X direction) is taken from the raw nonwoven fabric 10. cut. One heat fusion part 3 in the central region of the cut out rectangular measuring piece is selected. Next, as shown in FIG. 3, in order to measure the elongation at break in one selected heat-sealed portion 3, at the intermediate position in the longitudinal direction of the measurement piece in one heat-fused portion 3, A measurement sample is produced by making incisions extending in the horizontal direction from the respective side edges along the longitudinal direction of the rectangular measurement piece to the respective positions of both side edges of the single heat-sealed portion 3. The measurement sample is attached to a chuck of a tensile tester (for example, Tensilon tensile tester “RTA-100” manufactured by Orientec Co., Ltd.) so that the CD direction (X direction) is the tensile direction. The distance between chucks is 25 mm. The measurement sample is pulled at 100 mm / min, and the breaking elongation (%) at which the measurement sample breaks is measured. The elongation at break (%) is the ratio of the length that is increased by elongation at the time of rupture to the set distance between chucks. For example, the sample with the set distance between chucks of 25 mm is 50 mm. In the case of elongation and fracture, the elongation at break (%) is set to {(50-25) / 25} × 100 = 100%.

In the nonwoven fabric 1 of this embodiment, as shown in FIGS. 1 and 2, the heat fusion part 3 has a surface area of 0.05 mm ² or more and 10 mm from the viewpoint of touch and suitability for processing. preferably ² or less, still more preferably 0.1 mm ² or more 1 mm ² or less. The number of heat-sealing portions 3 is preferably 10 / cm ² or more and 250 / cm ² or less, and more preferably 35 / cm ² or more and 65 / cm ² or less. The distance between the centers of the heat fusion parts 3 adjacent in the X direction is preferably 0.5 mm or more and 10 mm or less, more preferably 1 mm or more and 3 mm or less, and the heat fusion part adjacent in the Y direction. The distance between the centers of the three is preferably 0.5 mm or more and 10 mm or less, and more preferably 1 mm or more and 3 mm or less.

  The heat fusion part 3 was intermittently formed by thermocompression bonding by embossing (by using an embossed convex roller and a flat roller), by ultrasonic welding, or intermittently heated and partially fused. Things. Among these, the one by thermocompression bonding is preferable because the fiber is easily broken. The shape of the heat-sealing portion 3 is not particularly limited, and may be any shape such as a circle, a rhombus, and a triangle in addition to the ellipse shown in FIG. The ratio of the total surface area of the heat fusion part 3 to the surface area of the one surface of the nonwoven fabric 1 is preferably 5% or more and 30% or less, preferably 10% or more and 20% or less, from the viewpoint that pills are difficult to be formed. Further preferred.

  As described above, the nonwoven fabric 1 of the present embodiment has a plurality of tear portions 4 formed by tearing the web. Then, a part of the plurality of tearing portions 4 is torn in an arc shape and the outer peripheral edge of the arc-shaped tearing portion 41 is rolled to form an opening 40 as shown in FIGS. ing. In the nonwoven fabric 1 of the present embodiment, as shown in FIG. 1, the plurality of tearing parts 4 include a first arc-shaped tearing part 41 that forms an opening 40, and an outer peripheral edge of the arc-shaped tearing part. It consists of a second arc-shaped tear portion 42 that is not twisted and a circular tear portion 43 that is torn in a circular shape. Here, the distinction between the first arc-shaped tearing portion 41 and the second arc-shaped tearing portion 42 is that the outer peripheral edge of the arc-shaped tearing portion is not flush with the outer surface of the nonwoven fabric 1, or above the outer surface of the nonwoven fabric 1 or The first arc-shaped tearing portion 41 is separated from the lower side, and the second arc-shaped tearing portion 42 is distinguished from the outer peripheral edge of the arc-shaped tearing portion being flush with the outer surface of the nonwoven fabric 1. Moreover, the circular tear part 43 is torn circularly and has a hole.

  In the nonwoven fabric 1 of this embodiment, the ratio of the 1st arc-shaped tear part 41 in the tear part 4 (the 1st arc-shaped tear part 41, the 2nd arc-shaped tear part 42, and the circular tear part 43) is air permeability, touch, From the viewpoint of processing suitability, it is preferably 30% or more, more preferably 45% or more, and preferably 100% or less, more specifically, 30% or more and 100% or less, preferably 45% or more and 100%. More preferably, it is as follows. The ratio of the first arc-shaped tear portions 41 can be obtained by observing with a microscope in which the number of the first arc-shaped tear portions 41 is enlarged 50 times.

In the nonwoven fabric 1 of this embodiment, the tearing part 4 (the 1st arc-shaped tearing part 41, the 2nd arc-shaped tearing part 42, and the circular tearing part 43) is each tearing part from a viewpoint of air permeability, a touch, and process appropriateness. The surface area of 4 is preferably ² mm ² or more and 10 mm ² or less, and more preferably 3 mm ² or more and 7 mm ² or less. The number of tearing parts 4 is preferably 5 / cm ² or more and 300 / cm ² or less, more preferably 10 / cm ² or more and 150 / cm ² or less. The number of tearing parts 4 is measured visually.

  In the nonwoven fabric 1 of this embodiment, the 1st arc-shaped tear part 41 which forms the opening part 40 in the tear part 4 is one of the perimeters of the heat-fusion part 3, as shown in FIG.2 and FIG.4. The long fibers 2 between the adjacent heat fusion parts 3 and 3 are torn along the peripheral edge 31 of the part. More specifically, the first arc-shaped tearing portion 41 is torn along a part of the peripheral edge 31 of the heat fusion portion 3, and the length between the heat fusion portions 3 and 3 adjacent to the heat fusion portion 3. The fiber 2 is torn and further torn along the peripheral edge 31 of a part of the adjacent heat-sealed portion 3, and they are connected to form an arc shape. In the nonwoven fabric 1 of the present embodiment, both the second arc-shaped tear portion 42 and the circular tear portion 43 in the tear portion 4 are within the entire circumference of the heat-sealed portion 3, similarly to the first arc-shaped tear portion 41. The long fibers 2 between the adjacent heat-sealing parts 3 and 3 are also torn along the peripheral edge 31 of the part.

  Moreover, the nonwoven fabric 1 of this embodiment is provided with the tear part 4 by which a web is torn, and as shown in FIG. 4, a part of long fiber 2 is fractured | ruptured, and only the one end part 20a is a heat-fusion part. 3 is provided with a raised fiber 20 fixed at 3 and having the other end side as a free end 20b. The nonwoven fabric 1 includes a raised fiber 20 having a free end portion 20b, and a loop-like fiber 23 that rises in a loop shape between heat-bonding portions 3 and 3 described later (the raised fiber 20 and the fiber 23 are combined to be “raised. It is made up of non-raised fibers other than “raised fibers”) and “raised fibers”. The nonwoven fabric 1 is mainly formed of fibers that are not raised. As shown in FIG. 4, the raised fiber 20 includes a fiber 21 whose free end portion 20b is thick and a fiber 22 whose free end portion 20b is not thick. As the fiber 21 having a thick tip, one having a flat cross section (ellipse or collapsed shape) at the tip is preferable. Here, the “free end portion” means “the other end portion” of the raised fiber 20 in which only the one end portion 20a is fixed by the heat fusion portion 3, in other words, the “tip portion”. . Whether or not the free end portion 20b is thick is determined by measuring the fiber diameter by the following measurement method and calculating the increasing rate of the tip fiber diameter.

[Measurement method of fiber diameter]
First, in a 22 ° C., 65% RH environment, as shown in FIG. 5 (a), a measurement piece having a size of 2 cm in the CD direction and 2 cm in the MD direction is taken from the nonwoven fabric 1 to be measured with a sharp razor. cut. When cutting out, it is preferable to remove the tear portion 4 as much as possible. Then, as shown in FIG. 5 (b), a measurement sample that is mountain-folded at a folding line Z that extends in the CD direction and passes through the plurality of heat-sealing portions 3 at a position where the tearing portion 4 is removed is shown in FIG. As shown in (c), it is placed and fixed on an aluminum sample stage for a scanning electron microscope (SEM) on which a carbon tape is placed. Next, from the SEM image magnified approximately 750 times, ten brushed fibers 20 in which only one end portion 20a is fixed by the heat fusion portion 3 are selected at random, and a photograph near the tip of the free end portion of these fibers. Take a picture. From the obtained photograph (see FIG. 6), the fiber diameter of the raised fiber 20 at the position 120 μm away from the tip of the free end 20b (the diameter 21a of the raised fiber 20 at the portion excluding the free end 20b) is measured. To do. The inclination at the time of measurement of the diameter 21a of the raised fiber 20 in the portion excluding the free end 20b is translated as it is to the free end 20b side, and between the tip of the free end 20b and a position 20 μm away from the tip. The fiber diameter of the fiber 21 at the thickest position in the sandwiched region (the diameter 21b of the fiber 21 at the free end 20b) is measured. When the tip is flat, the tip may not appear thick depending on the observation angle, but even in that case, the obtained photograph is measured as it is.

The fiber 21 whose free end 20b is thick is the raised fiber at the free end 20b measured from each of the 10 raised fibers 20 among the 10 randomly selected 10 raised fibers 20. From the diameter 21b of the fiber 20 and the diameter 21a of the raised fiber 20 at a portion excluding the free end 20b, the requirement that the value of the increase rate of the tip fiber diameter obtained by the following formula (1) is 15% or more is satisfied. This means that the fiber is filled, and the fiber cutting between the heat-bonding parts 3 (the fiber form part excluding the boundary between the heat-bonding part 3 and the fiber) is suppressed, and the decrease in breaking strength is suppressed. In view of obtaining a good touch, it is preferably 20% or more, more preferably 25% or more.

Increase rate of tip fiber diameter (%) = [((21b-21a) ÷ 21a) × 100] (1)

  In the nonwoven fabric 1, the raised fiber 20 (free end portion 20b) in which only one end portion 20a is fixed by the heat-sealing portion 3 from the viewpoint of achieving both the touch when touching the skin and the breaking strength and improving the cushioning property. The ratio of the fibers 21 in which the free ends 20b are thick in the fibers 21 in which the fibers 21 are thick and the fibers 22) in which the free ends 20b are not thick is preferably 20% or more, and 30% or more. More preferably, it is particularly preferably 40% or more. The ratio of the fiber 21 whose free end portion 20b is thick is the increase ratio of the tip fiber diameter from the SEM image obtained by enlarging the brushed fiber 20 selected at random 10 times about 750 times in the fiber diameter measurement method described above. Are calculated, and the ratio of the fibers 21 in which the free end portion 20b is thick is calculated.

  As described above, the nonwoven fabric 1 has the loop-like fibers 23 that stand in a loop shape between the heat-sealing portions 3 and 3 as shown in FIG. The standing “loop-like fiber 23” means that when the fiber diameter measurement method described above is observed as shown in FIG. 5C, the other end portion does not have the free end portion 20b, and the folded line It means a fiber standing up from Z by 0.5 mm or more.

The nonwoven fabric 1 configured as described above is inexpensive and can provide a good touch feeling, and from the viewpoint of processing suitability, the basis weight is preferably 5 g / m ² or more, and 100 g / It is preferably m ² or less, more preferably 25 g / m ² or less, specifically preferably 5 g / m ² or more and 100 g / m ² or less, and preferably 5 g / m ² or more and 30 g / m ² or less. More preferably.

Further, the nonwoven fabric 1 configured as described above has a bulk softness of preferably 10 cN or less, more preferably 5.5 cN or less, and more preferably 0.5 cN or more, from the viewpoint of excellent touch. Preferably there is.
In addition, the raw material nonwoven fabric 10 has a bulk softness of preferably 15 cN or less, more preferably 10 cN or less, and more preferably 3 cN or more from the viewpoint that a soft material is obtained and the touch is excellent and the opening is easy. Specifically, it is preferably 3 cN or more and 15 cN or less, and more preferably 3 cN or more and 10 cN or less.
Bulk softness is measured by the following measurement method.

[Measurement method of bulk softness]
The bulk softness of the nonwoven fabric 1 is obtained by cutting the nonwoven fabric 1 in the Y direction (longitudinal direction) 150 mm and the X direction (width direction) 30 mm in a 22 ° C. and 65% RH environment, and using a stapler in a ring shape with a diameter of 45 mm. Stop the edges at the top and bottom. At this time, the stapler core is elongated in the Y direction (longitudinal direction). Using a tensile tester (for example, Tensilon tensile tester “RTA-100” manufactured by Orientec Co., Ltd.), the ring is placed in a cylindrical shape on the sample stage, and the compression speed is 10 mm on a flat plate substantially parallel to the stage from above. Measure the maximum load when compressing at a rate of / min and make it bulk bulkiness.

In addition, the nonwoven fabric 1 configured as described above has an air permeability of preferably 750 m / Pa · s or more, more preferably 1000 m / Pa · s or more, from the viewpoint of excellent air permeability. And it is preferable that it is 3000 m / Pa * s or less. Specifically, it is preferably 750 m / Pa · s or more and 3000 m / Pa · s or less, and more preferably 1000 m / Pa · s or more and 3000 m / Pa · s or less.
The air permeability is obtained as the reciprocal of the airflow resistance measured by AUTOMATIC AIR-PERMEABILITY TESTER KES-F8-AP1 (breathability tester) manufactured by Kato Tech.

Moreover, the nonwoven fabric 1 comprised as mentioned above is 18.0 (gf / cm < ² >) / mm or less in the compression characteristic value at the time of the micro load from a viewpoint which is excellent in the touch, and 15.0 (gf / cm) ² ) / mm or less is more preferable. The lower limit of the compression characteristic value of the nonwoven fabric 1 is not particularly limited, but is about 1.00 (gf / cm ² ) / mm from the viewpoint of manufacturing.
The compression characteristic value at a minute load is measured by the following measuring method.

[Compression characteristic value at minute load]
The measurement of the data that is the basis for calculating the compression characteristic value at the time of a minute load is performed using KES FB3-AUTO-A (trade name) manufactured by Kato Tech Co., Ltd. in an environment of 22 ° C. and 65% RH. Specifically, three nonwoven fabrics 1 are cut into 20 cm × 20 cm to prepare measurement samples. Next, one of the measurement samples is placed on the test stand with the raised surface facing upward (if not raised, or if both surfaces are raised, measure both and adopt the smaller one). Next, it compresses between the steel plates of the circular plane of area 2cm < ² >. The compression speed is 20 μm / sec, the maximum compression load is 10 gf / cm ² , and the recovery process is also measured at the same speed. At this time, the displacement amount between the steel plates is set to x (mm), the load is set to y (gf / cm ² ), and the position of the point where the load is detected is set to x = 0 and measured in the compression direction. The value of x increases as it is compressed.

The compression characteristic value at the minute load is calculated by extracting the deformation amount of the thickness at the minute load from the measured data (x, y). Specifically, the first load which is not a recovery process, the load between 0.30 gf / cm ² and 1.00 gf / cm ² and the deformation data at that time are extracted, and the relationship between x and y is approximated A straight line is obtained by the least square method, and the slope at that time is defined as the characteristic value (unit (gf / cm ² ) / mm). Three points are measured with one measurement sample. A total of 9 points of 3 samples are measured. The characteristic values at each of the nine locations are calculated, and the average value is set as the compression characteristic value when the nonwoven fabric is subjected to a minute load.

  Next, the suitable manufacturing method of the nonwoven fabric 1 of this invention is demonstrated, referring FIGS. The manufacturing apparatus 200 that is preferably used in the method for manufacturing the nonwoven fabric 1 is broadly divided into a partially stretched portion 5 and a raised portion 6 disposed on the downstream side of the partially stretched portion 5.

  The partial extending | stretching process part 5 is provided with the steel matching embossing roller 53 which consists of a pair of uneven | corrugated rollers 51 and 52, as shown in FIGS. As shown in FIG. 8, the steel matching embossing roller 53 has a cylindrical shape made of metal such as aluminum alloy or steel, and one uneven roller 51 has a plurality of convex portions 511 on the peripheral surface, and the other The concave-convex roller 52 has a concave portion 522 into which the convex portion 511 enters at a position corresponding to the convex portion 511 of one concave-convex roller 51 on the peripheral surface. Further, as shown in FIG. 8, the other concavo-convex roller 52 has a plurality of convex portions 521 on the peripheral surface, and one concavo-convex roller 51 corresponds to the convex portion 521 of the other concavo-convex roller 52 on the peripheral surface. A concave portion 512 into which the convex portion 521 enters the position is provided. As shown in FIG. 8, the pair of concave and convex rollers 51 and 52 has convex portions 511 and 521 and concave portions 512 and 522 arranged in a staggered manner on the respective peripheral surfaces. The pair of concavo-convex rollers 51 and 52 mesh with each other and rotate when a driving force from a driving means (not shown) is transmitted to at least one of the rotation shafts. In the manufacturing apparatus 200 of the present embodiment, the one concavo-convex roller 51 and the other concavo-convex roller 52 are the same except that the convex portions 511 and 521 are provided at positions corresponding to the concave portions 522 and 512. Laura. Therefore, in the following description, the convex portion 511 of one concave-convex roller 51 will be mainly described with respect to similar portions. 7 and 8, for example, the partial stretching unit 5 includes transport rollers 54 and 55 used when transporting the raw material nonwoven fabric 10 on the upstream side and the downstream side of the steel matching embossing roller 53. Yes.

As shown in FIG. 9, each convex part 511 of the uneven roller 51 has a height h from the bottom of the uneven roller 51 to the apex of the convex part 511 of preferably 1 mm or more and 10 mm or less, and 2 mm or more and 7 mm or less. More preferably it is. The distance (pitch) between the protrusions 511 adjacent in the rotation axis direction is preferably 0.01 mm or more and 20 mm or less, more preferably 1 mm or more and 10 mm or less, and the distance between the protrusions 511 adjacent in the circumferential direction. The distance (pitch) P ₁ is preferably 0.01 mm or more and 20 mm or less, and more preferably 1 mm or more and 10 mm or less. There is no restriction | limiting in particular in the shape of the top surface of each convex part 511 of the uneven roller 51, For example, circular, a polygon, an ellipse etc. are used, The area of the top surface of each convex part 511 is the tear part with which the nonwoven fabric 1 is equipped. 4 (first arc-shaped tear portion 41, second arc-shaped tear portion 42 and circular tear portion 43) substantially corresponds to the surface area, easily forms the tear portion 4, and from the viewpoint of improving the softness of the nonwoven fabric after processing it is further preferred preferably at 1 mm ² or more 20 mm ² or less, and 2 mm ² or more 15 mm ² or less. Each concave portion 522 of the concave / convex roller 52 is disposed at a position corresponding to each convex portion 511 of the concave / convex roller 51. The depth d of engagement between the convex portions 511 of the concave-convex roller 51 and the convex portions 521 of the concave-convex roller 52 (the length of the portion where the convex portions 511 and the convex portions 521 overlap) (see FIG. 9) is 3.5 mm or more, preferably 3.7 mm or more, more preferably 4 mm or more, and 5 mm or less, specifically 3.5 mm or more and 5 mm or less, 3.7 mm. It is preferably 5 mm or less and more preferably 4 mm or more and 5 mm or less.

  As shown in FIGS. 7 and 10, the raised portion 6 includes a convex roller 61 having a convex portion 611 provided on the peripheral surface, and the nonwoven fabric 10 partially stretched on the upstream side and the downstream side of the convex roller 61. Conveying rollers 62 and 63 for conveying 'are provided. The convex roller 61 rotates when a driving force from a driving means (not shown) is transmitted to its rotating shaft.

Each convex portion 611 of the convex roller 61 has a height from the peripheral surface of the convex roller 61 to the apex of the convex portion 611 of preferably 0.001 mm or more and 3 mm or less, and 0.001 mm or more and 0.1 mm or less. More preferably. Since the convex roller 61 includes such a minute height, the convex roller 61 includes a so-called sand blast roller. The distance (pitch) between the protrusions 611 adjacent in the rotation axis direction is preferably 0.1 mm or more and 50 mm or less, more preferably 0.1 mm or more and 3 mm or less, and the protrusions 611 adjacent in the circumferential direction. The distance (pitch) between them is preferably from 0.1 mm to 50 mm, and more preferably from 0.1 mm to 3 mm. The shape of the top surface of each convex portion 611 of the convex roller 61 is not particularly limited. For example, a circular shape, a polygonal shape, an elliptical shape or the like is used, and the area of the top surface of each convex portion 611 is 0.001 mm ² or more and 20 mm. preferably ² or less, still more preferably 0.01 mm ² or more 1 mm ² or less. When the convex roller 61 is a sand blast roller, the density of the convex portions 611 is preferably 1000 / cm ² or more and 3000 / cm ² or less, and preferably 1200 / cm ² or more and 2500 / cm ^2. More preferably, it is as follows.

  As shown in FIG. 7, the manufacturing apparatus 200 includes a winding roller (not shown) that winds the nonwoven fabric 1 manufactured on the downstream side of the raised portion 6, and winds the winding roller (not shown). An outfeed roller 7 for conveying the previous nonwoven fabric 1 is provided. The outfeed roller 7 can measure the conveyance speed of the nonwoven fabric 1.

Next, one embodiment of the method for producing a nonwoven fabric of the present invention will be described using the production apparatus 200 described above with reference to FIG.
In this embodiment, the raw material nonwoven fabric 10 in which the web including the long fibers 2 is fixed by the heat fusion part 3 is supplied between the pair of concave and convex rollers 51 and 52, and a plurality of portions of the nonwoven fabric 10 are partially stretched. It is a manufacturing method of a nonwoven fabric. In the present embodiment, the raw nonwoven fabric 10 is stretched at a strain rate of 1 × 10 ² s ⁻¹ or more in a partial stretching process, and has a plurality of tear portions 4 formed by tearing a web containing long fibers, A part of the plurality of tear portions 4 is torn in an arc shape, and the outer peripheral edge of the arc-shaped tear portion is rolled to form the nonwoven fabric 1 forming the opening 40. This will be specifically described below.

  In the manufacturing method of the nonwoven fabric of this embodiment, from the viewpoint of ease of cutting the fibers around the heat-sealed portion in order to make the openings open, when the partial stretching process is performed on each of a plurality of locations of the raw material nonwoven fabric 10, It is preferable to process at temperature. The temperature of 50 ° C. or lower means that the temperature is not normal when the rollers 51 and 52 are not actively heated and the raw nonwoven fabric 10 is stretched. In other words, when the raw nonwoven fabric 10 is partially stretched, any kind of constituent fiber resin can be used from the viewpoint that the raw nonwoven fabric 10 does not become hard due to heat fusion between the constituent fibers of the nonwoven fabric. It means that the temperature is lower than the melting point.

  In the manufacturing method of the nonwoven fabric of this embodiment, first, the belt-shaped raw material nonwoven fabric 10 is unwound from the raw fabric roll 10R, and the raw material nonwoven fabric 10 is steel-matched via conveying rollers 54 and 55 as shown in FIG. It conveys between a pair of uneven | corrugated rollers 51 and 52 of the embossing roller 53, and performs a partial extending | stretching process to the raw material nonwoven fabric 10. FIG. More specifically, the conveyed raw material nonwoven fabric 10 includes a plurality of convex portions 511 included in one concave-convex roller 51 and a plurality of concave portions 522 included in the other concave-convex roller 52 shown in FIGS. 8 and 9. Nipping between the plurality of convex portions 521 of the other concave-convex roller 52 and the plurality of concave portions 512 of the one concave-convex roller 51, and conveying to each of a plurality of locations of the raw material nonwoven fabric 10 Stretching is performed in a direction perpendicular to the direction and the conveying direction.

In this embodiment, in order to efficiently cut the fiber in forming a plurality of tear portions 4 by partial stretching and forming the first arc-shaped tear portion 41 having the opening 40 among the tear portions 4. It is important to lower the elongation at break. The elongation at break decreases as the strain rate increases. From the viewpoint of the viscoelasticity of the raw material nonwoven fabric, for example, when polypropylene is used as the raw material, the strain elongation greatly decreases at a strain rate of 1 × 10 ² s ⁻¹ or more. . Accordingly, the raw nonwoven fabric 10 is preferably stretched at a strain rate of 1 × 10 ² s ⁻¹ or more, and the raw nonwoven fabric 10 is more preferably stretched at a strain rate of 1 × 10 ³ s ⁻¹ or more. The upper limit is preferably 5 × 10 ³ s ⁻¹ or less. Here, as shown in FIG. 9, the strain rate means that the raw material nonwoven fabric 10 is conveyed between a pair of concave and convex rollers 51 and 52 and is subjected to partial stretching processing immediately before the convex portion 511 of one concave and convex roller 51 and the other. The time until immediately after the concave portion 522 of the concave-convex roller 52 meshes to the maximum and performs the partial stretching process, in other words, the convex portion 511 of one concave-convex roller 51 and the convex portion 521 of the other concave-convex roller 52 are closest to each other. It means how much the raw material nonwoven fabric 10 is deformed during the time from when the convex portion 511 of one concave-convex roller 51 and the convex portion 521 of the other concave-convex roller 52 are positioned perpendicular to each other. The strain rate is obtained by the following equation (2).

Strain rate V [s ⁻¹ ] = Indentation rate Vx / Length L ₀ of the first raw material nonwoven fabric (2)

Here, the length L ₀ of the first raw material non-woven fabric is the distance between the pair of concave and convex rollers 51 and 52 when the convex portion 511 of one concave and convex roller 51 and the convex portion 521 of the other concave and convex roller 52 are closest to each other. It means the length in the conveyance direction of the conveyed raw material nonwoven fabric 10 (see FIG. 9). In addition, when R shape is given to the edge part of the top part of the convex parts 511 and 521 of the uneven | corrugated rollers 51 and 52, for example, the extension line of the side along the side surface when the convex parts 511 and 521 are viewed from the side And the intersection of the top of the projections 511 and 521 and the extension of the top edge along the top surface when viewed from the side is determined as the virtual edge portion of the top of the projections 511 and 521.

Further, the indentation speed Vx according to the above equation (2) is obtained by the following equation (3).

Indentation speed Vx = Drawing amount D / Time tmax until the concavo-convex roller meshes to the maximum t (3)

Here, the stretching amount D means that when the convex portion 511 of one concave-convex roller 51 and the convex portion 521 of the other concave-convex roller 52 are positioned perpendicular to each other, that is, the convex portion 511 of one concave-convex roller 51 is the other. It means the length in the transport direction of the raw nonwoven fabric 10 transported between the pair of concave and convex rollers 51 and 52 when the concave and convex rollers 52 are engaged with the concave portion 522 at the maximum (see FIG. 9). Further, the time tmax until the maximum engagement is established means that the convex portion 511 of one concave-convex roller 51 and the convex portion 521 of the other concave-convex roller 52 are closest to the convex portion 511 of one concave-convex roller 51 and the other. It means the time until the convex portions 521 of the uneven roller 52 are positioned perpendicular to each other. In addition, when R shape is given to the edge part of the top part of the convex parts 511 and 521 of the uneven | corrugated rollers 51 and 52, as mentioned above, a virtual edge part is assumed and judged.

Further, the time tmax until the concave and convex rollers according to the above formula (3) are engaged with each other is obtained by the following formula (4).

Time tmax until the concavo-convex roller meshes to the maximum
= Distance Lmax until uneven roller meshes to maximum / Processing speed (4)

Here, the distance Lmax until the concavo-convex roller meshes to the maximum is the convex portion of one concavo-convex roller 51 from the position where the convex portion 511 of one concavo-convex roller 51 and the convex portion 521 of the other concavo-convex roller 52 are closest. 511 and the distance to the position where the convex portions 521 of the other concave-convex roller 52 are perpendicular to each other. Moreover, a processing speed means the conveyance speed of a nonwoven fabric.
In addition, when R shape is given to the edge part of the top part of the convex parts 511 and 521 of the uneven | corrugated rollers 51 and 52, as mentioned above, a virtual edge part is assumed and judged.

  Further, in the present embodiment, from the viewpoint of efficiently forming the first arc-shaped tearing portion 41 having the opening 40 in the tearing portion 4 by forming a plurality of tearing portions 4 by partial stretching processing, The draw ratio (V2 / V1) of the transport speed (V2) of the manufactured nonwoven fabric 1 with respect to the peripheral speed (V1) at the top of the convex portion 511 is preferably 1.2 or more, and is 1.3 or more. More preferably. Here, the conveyance speed (V2) of the nonwoven fabric 1 is a speed measured by the outfeed roller 7 provided in the manufacturing apparatus 200. In this embodiment, the conveyance speed (V2) measured by the outfeed roller 7 is the same speed not only on the downstream side of the raised portion 6 but also on the downstream side of the partially extending portion 5.

  Next, in this embodiment, the raw material nonwoven fabric 10 ′ after the partial stretching process is subjected to a raising process for raising the constituent fibers of the raw material nonwoven fabric 10. More specifically, the raw material nonwoven fabric 10 ′ that has been partially stretched to form the tearing portion 4 is subjected to raising processing for raising the constituent fibers of the raw material nonwoven fabric 10. More specifically, the raw material nonwoven fabric 10 ′ that has been partially stretched and formed with the tearing portion 4 is conveyed to the convex roller 61 via the conveying rollers 62 and 63 as shown in FIG. 7. And in the raising process part 6, using the convex roller 61 which has the convex part 611 in a surrounding surface, a part of long fiber 2 which comprises the raw material nonwoven fabric 10 is fractured | ruptured, and only the one end part 20a makes the raw material nonwoven fabric 10 The nonwoven fabric 1 which has the raising fiber 20 currently fixed by the heat-sealing part 3 to comprise and has several tearing parts 4 is manufactured continuously (refer FIG.2 and FIG.4). From the viewpoint of breaking a part of the long fiber 2 and efficiently forming the raised fiber 20 shown in FIG. 4, the rotation direction of the convex roller 61 can be rotated in the opposite direction to the conveying direction of the raw material nonwoven fabric 10 ′. Preferably, the convex roller 61 is rotated at a speed not less than 0.3 times and not more than 10 times the transport speed of the raw material nonwoven fabric 10 ′. Further, when rotating in the circumferential direction (forward direction with respect to the conveying direction), it is preferable to rotate the convex roller 61 at a speed of 1.5 to 20 times. Here, the speed of the convex roller 61 means the peripheral speed on the peripheral surface of the convex roller 61.

  In addition, when forming the raised fiber 20 in which only one end portion 20a is fixed by the heat fusion part 3 on both surfaces of the nonwoven fabric 1, the surface (back surface) is different from the surface of the raw material nonwoven fabric 10 ′ processed by the convex roller 61. ) Is further processed by another convex roller 61.

  In the raising process, the fiber 21 in which the free end portion 20b of the raised fiber 20 is thick is partially stretched by the steel matching embossing roller 43 to weaken the heat-bonded portion 3 of the material nonwoven fabric 10. A point is formed, and then the long fiber 2 is broken and formed by the convex roller 61 from the weakening point of the very surface portion of the raw material nonwoven fabric 10 ′ of the heat fusion part 3. Further, when the surface of the fiber 22 which is not thick at the free end 20b of the raised fiber 20 is processed by the convex roller 61, the long fiber 2 is broken between the heat-sealing portions 3 and 3. It is formed. Moreover, the long fiber 2 peels from the weakening point of the heat-fusion part 3 by the convex roller 61, and the fiber peeled from the heat-fusion part 3 is looped between the heat-fusion parts 3 and 3. What stands is a loop-like fiber 23. The nonwoven fabric manufactured by the suitable manufacturing method of the nonwoven fabric 1 mentioned above is characterized in that the proportion of the loop-like fibers 23 and the fibers 22 that are not thick is smaller than the nonwoven fabric manufactured by the conventional raising method. . Since the nonwoven fabric manufactured with the suitable manufacturing method of the nonwoven fabric 1 mentioned above has few ratios of the fiber 22 which is not thick, it can hold | maintain breaking strength.

The effect at the time of using the nonwoven fabric 1 of embodiment of this invention mentioned above is demonstrated.
As shown in FIGS. 1, 2, and 4, the nonwoven fabric 1 of the present embodiment has a plurality of tear portions 4 formed by tearing the web, and a part of the plurality of tear portions 4 is The outer peripheral edge of the arc-shaped tearing portion 41 is rolled to form the opening 40. Therefore, high air permeability can be ensured, and the opening 40 is not formed by melting and is formed by tearing, so that the touch is good. Moreover, since the opening 40 of the nonwoven fabric 1 is formed in a shape in which the outer peripheral edge of the arc-shaped tearing portion 41 is curled, it is difficult to wet back, in particular, it can be expected that liquid return of soft stool is difficult, and penetrates. The quality of the nonwoven fabric is improved, making it difficult to associate holes.

  Moreover, the 1st arc-shaped tear part 41 which forms the opening part 40 which the nonwoven fabric 1 of this embodiment has is torn along the one part periphery 31 of the heat-fusion part 3, as shown in FIG.2 and FIG.4. The long fiber 2 between the heat fusion portions 3 and 3 adjacent to the heat fusion portion 3 is torn, and is further torn along the peripheral edge 31 of a part of the adjacent heat fusion portion 3. Repeatedly, they are connected to form an arc. In addition, as shown in FIG. 1, the plurality of tearing portions 4 included in the nonwoven fabric 1 of the present embodiment are torn apart in an arc shape other than the first arc-shaped tearing portion 41 that forms the opening 40, and the arc-shaped tearing portion 4 It has the 2nd arc-shaped tear part 42 in which the outer periphery is not curled, and the circular tear part 43 torn in the circular shape. Therefore, there is an effect that liquid return of soft stool is improved.

  Moreover, the nonwoven fabric 1 of this embodiment is provided with the tear part 4 by which a web is torn, as shown in FIG. 4, a part of long fiber 2 is fractured | ruptured, and only the one end part 20a is a heat-fusion part. 3 is further provided with raised fibers 20 fixed by 3 and having the other end portion as a free end portion 20b. Therefore, the touch is further improved.

  And according to the manufacturing method of the nonwoven fabric of this embodiment mentioned above, while ensuring high air permeability, the touch is good, it is difficult to wet back, and in particular, it is expected that it is difficult to return the liquid of soft stool. The nonwoven fabric 1 which is difficult to associate and improved in quality can be produced efficiently and continuously.

The range of use of the nonwoven fabric 1 is suitably used mainly for constituent members in absorbent articles such as disposable diapers and sanitary napkins. Examples of the constituent member include a surface sheet, a back sheet, a sheet constituting an outer packaging material of the disposable diaper, and the nonwoven fabric 1 is particularly suitable for a surface sheet of an absorbent article used for a wearer's skin contact surface. Used for. The use range of the nonwoven fabric 1 is also suitably used for a cleaning sheet. When used for a cleaning sheet, the sheet is excellent in dust collection.
Hereinafter, the disposable diaper using the nonwoven fabric 1 will be described as an example.

As shown in FIGS. 11 and 12, the pants-type disposable diaper 100 is located on the non-skin contact surface side of the absorbent main body 8 including the absorbent body 81 and fixes the absorbent main body 8. The outer packaging material 9 is provided.
As shown in FIG. 12, the absorbent main body 8 includes a liquid-permeable top sheet 82, a liquid-impermeable (including water-repellent) back sheet 83, and a liquid-retaining property interposed between both sheets 82 and 83. It has the absorber 81 and is substantially vertically long as shown in FIG.
As shown in FIG. 11, the outer packaging material 9 includes a back side portion A disposed on the back side of the wearer, an abdominal side portion B disposed on the abdomen side, and an inseam located between the crotch portions. It has a portion C, and both side edge portions 9a and 9b of the back side portion A and the ventral side portion B are joined to each other to form a pair of side seal portions (not shown) and a pair of leg openings (not shown). And a waist opening (not shown). The outer packaging material 9 includes an outer layer sheet 92 that forms the outer surface of the diaper, and an inner layer sheet 91 that is located on the skin contact surface side and is partially joined to the outer layer sheet 92, and has a waist opening. Also, a waist elastic member 93 and a leg elastic member 94 for gathering are arranged between the sheets 91 and 92 in the waist and leg 9d forming the leg opening.

As shown in FIG. 11, the absorbent main body 8 is disposed from the back side portion A to the abdominal side portion B of the outer packaging material 9, and both end portions in the longitudinal direction of the absorbent main body 8 are arranged on the outer packaging material 9. It is in the position retreated inward in the longitudinal direction from both ends in the longitudinal direction. As shown in FIG. 12, the absorbent main body 8 has a non-skin contact surface of the back sheet 83 of the absorbent main body 8 such that the inner layer sheet 91 of the outer packaging material 9 is bonded by an adhesive, heat seal, ultrasonic seal or the like. It is joined to the skin contact surface.
As shown in FIG. 12, side cuffs 84 and 84 made of a liquid-impermeable or water-repellent and breathable material are provided on both side portions along the longitudinal direction of the absorbent main body 8. In the vicinity of the free end of each side cuff 84, an elastic member 85 for forming the side cuff is disposed and fixed in an extended state. The side cuff 84 stands up at the free end when the diaper is worn, and can prevent excrement from flowing out in the width direction of the absorbent main body 8. In the side cuff 84 forming sheet, as shown in FIG. 12, a portion of the absorbent body 8 having a predetermined width on the outer side in the width direction is wound around the non-skin contact surface side of the absorbent body 81. And the back sheet 83. In addition, the part of the predetermined width may be fixed between the back sheet 30 and the outer packaging material 9.

  The nonwoven fabric 1 of this embodiment is preferably used as the outer layer sheet 92 and the inner layer sheet 91 of the outer packaging material 9 of the pants-type disposable diaper 100 used on the skin contact surface of the wearer. Moreover, it can also be used as a sheet for forming the top sheet 82, the back sheet 83, and the side cuffs 84. As the member of each part when the nonwoven fabric 1 is not used, those used for absorbent articles such as disposable diapers can be used without particular limitation. For example, as the top sheet 82, a liquid-permeable nonwoven fabric, a perforated film, a laminate of these, or the like can be used. As the back sheet 83, a resin film or a laminate of a resin film and a nonwoven fabric can be used. Can do. As the sheet for forming the side cuff 84, a stretchable film, a nonwoven fabric, a woven fabric, or a laminated sheet thereof can be used. As the inner layer sheet 91 and the outer layer sheet 92, a water-repellent nonwoven fabric or the like can be used.

As the absorbent body 81, those conventionally used for absorbent articles such as disposable diapers can be used without particular limitation. For example, as the absorbent body 81, a fiber aggregate of fiber materials such as pulp or a material in which a superabsorbent polymer is supported and wrapped with a covering material such as tissue paper or a water-permeable nonwoven fabric is used. Can be used.
As the elastic member 85 for forming side cuffs, the waist elastic member 93, and the leg elastic member 94, those normally used for absorbent articles such as disposable diapers can be used without particular limitation. For example, a stretchable material made of natural rubber, polyurethane, polystyrene-polyisoprene copolymer, polystyrene-polybutadiene copolymer, polyethylene-α olefin copolymer such as ethyl acrylate-ethylene, or the like can be used.

The nonwoven fabric of this invention is not restrict | limited to the nonwoven fabric 1 of the above-mentioned this embodiment at all, and can be changed suitably.
Moreover, the manufacturing method of the nonwoven fabric of this invention is not restrict | limited at all to the manufacturing method of the above-mentioned embodiment, It can change suitably.

For example, as shown in FIGS. 2 and 4, the nonwoven fabric 1 of the above-described embodiment includes the tearing portion 4 formed by tearing the web and the raised fiber 20, but does not include the raised fiber 20. May be. When manufacturing the nonwoven fabric provided with the tearing part 4 without providing such a raising fiber 20, in the manufacturing method of the nonwoven fabric 1 of the above-mentioned this embodiment, it does not have the raising process part 6, but has the partial extending | stretching process part 5. FIG. It can manufacture by using a manufacturing apparatus.
Moreover, in the manufacturing method of the nonwoven fabric 1 of this embodiment mentioned above, as shown in FIG. 7, the raising process which raises the constituent fiber of this nonwoven fabric 10 'is given to nonwoven fabric 10' after performing a partial extending | stretching process. Although the nonwoven fabric 1 is manufactured, the raw nonwoven fabric 10 before the partial stretching process is subjected to a raising process for raising the constituent fibers of the nonwoven fabric 10, and then the partial stretching process is performed to manufacture the nonwoven fabric 1. Good.

  Moreover, the 1st arc-shaped tear part 41 which forms the opening part 40 which the nonwoven fabric 1 of this embodiment has is torn along the one part periphery 31 of the heat-fusion part 3, as shown in FIG.2 and FIG.4. Furthermore, although the long fiber 2 between the adjacent heat-sealing parts 3 and 3 is torn and formed, it is not restricted to the form. Moreover, the tear part 4 which the nonwoven fabric 1 of this embodiment has is formed from the 1st arc-shaped tear part 41, the 2nd arc-shaped tear part 42, and the circular tear part 43, but has only the 1st arc-shaped tear part 41. It only has to be.

Moreover, you may give a small amount of additives, such as an antistatic property agent, a lubricant, and a hydrophilic agent, to the fiber which comprises the raw material nonwoven fabric 10. FIG.
Moreover, it is preferable that the raw material nonwoven fabric 10 is heat-processed at the temperature below melting | fusing point of the fiber which comprises the raw material nonwoven fabric 10 from a viewpoint of raising a plump feeling and improving a touch feeling, and it is preferable that it is especially hot-air processing.

  The following nonwoven fabric and its manufacturing method are further disclosed regarding the embodiment mentioned above.

<1>
A non-woven fabric formed from a web containing long fibers,
A plurality of tearing portions formed by tearing the web;
A part of the plurality of tear portions is torn in an arc shape, and an outer peripheral edge of the arc-shaped tear portion is rolled to form an opening.

<2>
The non-woven fabric is a non-woven fabric formed by fixing the web with a heat-sealing part,
The first arc-shaped tearing portion that forms the opening is torn along a part of the circumference of the entire circumference of the heat-sealing portion, and the long fibers between the adjacent heat-sealing portions are further separated. The nonwoven fabric according to <1>, which is formed by tearing.
<3>
The plurality of tear portions were torn in a circular shape, a first arc-shaped tear portion that forms the opening, a second arc-shaped tear portion that was torn in an arc shape and the outer peripheral edge of the arc-shaped tear portion was not bent The nonwoven fabric according to <1> or <2>, comprising a circular tear portion.
<4>
Similar to the first arc-shaped tearing portion 41, the second arc-shaped tearing portion and the circular tearing portion are also torn along a part of the periphery of the heat-sealed portion and further adjacent to each other. The nonwoven fabric according to any one of <1> to <3>, wherein the long fibers between the heat-sealed portions are torn.
<5>
The nonwoven fabric according to <3>, wherein a ratio of the first arc-shaped tear portion in the tear portion is 30% or more.
<6>
The nonwoven fabric according to any one of <1> to <5>, wherein a ratio of the first arc-shaped tear part in the tear part is 30% or more, preferably 45% or more, and preferably 100% or less.
<7>
The non-woven fabric according to any one of <1> to <6>, wherein a surface area of the tear portion is preferably 2 mm ² or more and 10 mm ² or less, more preferably 3 mm ² or more and 7 mm ² or less.
<8>
The number of the tear parts is 5 / cm ² or more and 300 / cm ² or less, preferably 10 / cm ² or more and 150 / cm ² or less, according to any one of <1> to <7>. Non-woven fabric.

<9>
Any of the above <1> to <8>, comprising a raised fiber in which a part of the long fiber is broken, only one end is fixed by the heat fusion part, and the other end is a free end Or the nonwoven fabric according to 1.
<10>
The raised fiber is a non-woven fabric according to any one of <1> to <9>, including a fiber having a thick free end and a fiber having a thick free end.
<11>
The fiber with the thickened tip is the nonwoven fabric according to any one of <1> to <10>, wherein a cross section at the tip is flat (ellipse or crushed shape).
<12>
The ratio of the fibers in which the free end portion is thick in the raised fibers is preferably 20% or more, more preferably 30% or more, and particularly preferably 40% or more. The nonwoven fabric according to any one of> to <11>.
<13>
The nonwoven fabric according to any one of <1> to <12>, wherein the bulk softness of the nonwoven fabric is 10 cN or less, preferably 5.5 cN or less, and 0.5 cN or more.
<14>
The nonwoven fabric preferably has an air permeability of 750 m / Pa · s or more, more preferably 1000 m / Pa · s or more, and <1> to <13, which is 3000 m / Pa · s or less. > Any one of>.
<15>
The nonwoven fabric has a compressive property value at a minute load of 18.0 (gf / cm ² ) / mm or less, preferably 15.0 (gf / cm ² ) / mm or less, and 1.00 (gf / cm ² ) The nonwoven fabric according to any one of <1> to <14>, which is not less than / mm.
<16>
An absorbent article using the nonwoven fabric according to any one of <1> to <15> as a constituent member.

<17>
A raw material nonwoven fabric in which a web containing long fibers is fixed by a heat-sealing part is supplied between a pair of concavo-convex rollers, and a method for producing a nonwoven fabric in which a plurality of portions of the nonwoven fabric are partially stretched,
In the partial stretching process, the raw material nonwoven fabric is stretched at a strain rate of 1 × 10 ² s ⁻¹ or more,
It has a plurality of tear parts formed by tearing a web containing long fibers,
A method of manufacturing a nonwoven fabric, wherein a part of the plurality of tear portions is torn in an arc shape and an outer peripheral edge of the arc-shaped tear portion is rolled to form an opening portion.

<18>
In the partial stretching process, the raw nonwoven fabric is stretched at a strain rate of 1 × 10 ² s ⁻¹ or higher, preferably 1 × 10 ³ s ⁻¹ or higher, and strain of 5 × 10 ³ s ⁻¹ or lower. The method for producing a nonwoven fabric according to <17>, wherein the nonwoven fabric is stretched at a speed.
<19>
In the pair of concave and convex rollers, one roller has a plurality of convex portions on the peripheral surface, and the other roller has a concave portion in which the convex portion enters the peripheral surface at a position corresponding to the convex portion of the one roller. Have
<7> or <7>, wherein a draw ratio (V2 / V1) of a conveyance speed (V2) of the manufactured nonwoven fabric to a peripheral speed (V1) at the top of the convex portion of the one roller is 1.2 or more. The manufacturing method of the nonwoven fabric as described in <8>.
<20>
The draw ratio (V2 / V1) of the transport speed (V2) of the manufactured nonwoven fabric to the peripheral speed (V1) at the top of the convex portion of one of the rollers is preferably 1.2 or more. It is still more preferable that it is 3 or more, The manufacturing method of the nonwoven fabric any one of said <17>-<19>.
<21>
The convex portion of one of the rollers preferably has a height h from the bottom of the one roller to the apex of the convex portion of 1 mm or more and 10 mm or less, and more preferably 2 mm or more and 7 mm or less. The manufacturing method of the nonwoven fabric any one of <1>-<20>.
<22>
The distance (pitch) between the convex portions of one of the rollers adjacent to the rotation axis direction is preferably 0.01 mm or more and 20 mm or less, more preferably 1 mm or more and 10 mm or less, and adjacent in the circumferential direction. The distance (pitch) P ₁ between the convex portions of one of the rollers is preferably 0.01 mm or more and 20 mm or less, more preferably 1 mm or more and 10 mm or less. <17> to <21> The manufacturing method of the nonwoven fabric any one of these.
<23>
The depth d of engagement between the convex portion of one of the rollers and the convex portion of the other roller is 3.5 mm or more, preferably 3.7 mm or more, and more preferably 4 mm or more. The method for producing a nonwoven fabric according to any one of <17> to <22>, which is preferably 5 mm or less.
<24>
Any one of said <17>-<23> using the nonwoven fabric whose breaking elongation of the direction orthogonal to the orientation direction of the said long fiber in one said heat-fusion part is 45% or less as said raw material nonwoven fabric. The manufacturing method of the nonwoven fabric as described in any one of.
<25>
As the raw material nonwoven fabric, the elongation at break in the direction (X direction) perpendicular to the orientation direction of the long fibers in one heat-sealed part is 45% or less, preferably 35% or less, more preferably 30% or less. Yes, The manufacturing method of the nonwoven fabric any one of said <17>-<24> using the nonwoven fabric which is 5% or more.
<26>
The said partial extending | stretching process is a manufacturing method of the nonwoven fabric any one of said <17>-<25> performed at the temperature of 50 degrees C or less.
<27>
Any one of the above items <17> to <26>, wherein the raw material nonwoven fabric before the partial stretching process or the nonwoven fabric after the partial stretching process is subjected to a raising process for raising constituent fibers of the nonwoven fabric. The manufacturing method of the nonwoven fabric as described.

<28>
The raising process is performed using a convex roller provided with a convex portion on the peripheral surface,
The height of the convex portion of the convex roller from the peripheral surface of the convex roller to the apex of the convex portion is preferably 0.001 mm or more and 3 mm or less, and is 0.001 mm or more and 0.1 mm or less. The method for producing a nonwoven fabric according to any one of <17> to <27>, wherein is more preferable.
<29>
The method for producing a nonwoven fabric according to any one of <17> to <28>, wherein the convex roller is rotated at a speed of 0.3 to 10 times the transport speed of the raw material nonwoven fabric.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.

[Example 1]
As a raw material nonwoven fabric, a spunbonded nonwoven fabric having a basis weight of 17 g / m ^{2 made} of polypropylene resin having a fiber diameter of 15 μm was used. In addition, the breaking elongation of the X direction of one heat-sealing part 3 measured based on the measuring method of the breaking direction of the X direction of one heat-fusion part 3 in the raw material nonwoven fabric mentioned above is 27%. there were. Moreover, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 5.4 cN. Next, this spunbond nonwoven fabric was passed through a steel matching embossing roller 53 shown in FIGS. The conveyance speed of the nonwoven fabric by the outfeed roller 7 is 1000 m / min, the distance Lmax until the concave and convex rollers are meshed to the maximum is 22 mm, the stretching amount D is 4.0 mm, and the length L of the first raw material nonwoven fabric L ₀ was 1.0 mm. From these values, the strain rate was obtained using the above-mentioned formulas (2), (3), and (4), and is shown in Table 1. Further, the peripheral speed V1 at the top of the convex part of the uneven roller was 728 m / min. The draw ratio (V2 / V1) was determined from this value and the value of the above-mentioned nonwoven fabric conveyance speed, and shown in Table 1. Moreover, the height of each convex part 511 of the roller 51 in the used steel matching embossing roller 53 is 5 mm, and the distance (pitch P ₁ ) between the convex parts 511 adjacent to each other in the circumferential direction is 8 mm. The distance (pitch P ₂ ) between the adjacent convex portions 511 was 8 mm. The same applies to the convex portions 521 in the roller 52 of the steel matching embossing roller 53.

[Example 2]
The nonwoven fabric of Example 2 was produced under the same conditions as in Example 1 except that the same raw material nonwoven fabric as in Example 1 was used and the nonwoven fabric conveyance speed at the outfeed roller 7 was 200 m / min. As in Example 1, the strain rate was determined using the above-described formulas (2), (3), and (4) and shown in Table 1.

Example 3
Example 1 except that the same raw material nonwoven fabric as in Example 1 was used, the distance Lmax until the concave and convex rollers meshed to the maximum was 22 mm, and the peripheral speed V1 at the top of the convex portion of the concave and convex rollers was 744 m / min. The nonwoven fabric of Example 3 was produced by partially stretching under the same conditions as above and further raising the raised portions with the convex rollers 61 in which the convex portions 611 were arranged in a random pattern. As in Example 1, the strain rate was determined using the above-described formulas (2), (3), and (4) and shown in Table 1. Further, similarly to Example 1, the draw ratio (V2 / V1) was obtained and shown in Table 1. The density of the convex portions 611 of the convex roller 61 was 2000 / cm ² .

Example 4
As the raw material nonwoven fabric, a spunbonded nonwoven fabric having a basis weight of 20 g / m ^{2 made} of polypropylene resin having a fiber diameter of 16 μm was used. In addition, the breaking elongation of the X direction of one heat-sealing part 3 measured based on the measuring method of the breaking direction of the X direction of one heat-fusion part 3 in the raw material nonwoven fabric mentioned above is 27%. there were. Moreover, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 7.4 cN. The conveyance speed of the nonwoven fabric at the outfeed roller 7 is 800 m / min, the distance Lmax until the concave and convex rollers are engaged with each other is 22 mm, and the peripheral speed V1 at the top of the convex portion of the concave and convex rollers is 612 m / min. The nonwoven fabric of Example 4 was produced under the same conditions as in Example 1. As in Example 1, the strain rate was determined using the above-described formulas (2), (3), and (4) and shown in Table 1. Further, similarly to Example 1, the draw ratio (V2 / V1) was obtained and shown in Table 1.

Example 5
As the raw material nonwoven fabric, a spunbonded nonwoven fabric having a basis weight of 18 g / m ^{2 made} of polypropylene resin having a fiber diameter of 16 μm was used. In addition, the breaking elongation in the X direction of one heat-sealing part 3 measured based on the measuring method of the breaking direction in the X direction of one heat-sealing part 3 in the raw material nonwoven fabric described above is 43%. there were. Moreover, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 3.2 cN. The nonwoven fabric is conveyed at a speed of 600 m / min at the outfeed roller 7 and partially stretched under the same conditions as in Example 1 except that the circumferential speed V1 at the top of the convex portion of the concavo-convex roller is 439 m / min. Further, the nonwoven fabric of Example 5 was produced by raising the raised portions 611 with raised rollers 61 in which the raised portions 611 were arranged in a random pattern. As in Example 1, the strain rate was determined using the above-described formulas (2), (3), and (4) and shown in Table 1. Further, similarly to Example 1, the draw ratio (V2 / V1) was obtained and shown in Table 1.

Example 6
As a raw material nonwoven fabric, a spunbonded nonwoven fabric having a basis weight of 17 g / m ^{2 made} of polypropylene resin having a fiber diameter of 15 μm was used. In addition, the breaking elongation of the X direction of one heat-sealing part 3 measured based on the measuring method of the breaking direction of the X direction of one heat-fusion part 3 in the raw material nonwoven fabric mentioned above is 25%. there were. Moreover, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 11.6 cN. The non-woven fabric is conveyed at a speed of 400 m / min at the outfeed roller 7 and partially stretched under the same conditions as in Example 1 except that the circumferential speed V1 at the top of the convex portion of the uneven roller is 319 m / min. Further, the nonwoven fabric of Example 6 was produced by raising the raised portions 611 with raised rollers 61 arranged in a random pattern. As in Example 1, the strain rate was determined using the above-described formulas (2), (3), and (4) and shown in Table 1.

[Comparative Example 1]
As the nonwoven fabric of Comparative Example 1, a spunbonded nonwoven fabric having a basis weight of 17 g / m ^{2 made} of polypropylene resin having a fiber diameter of 15 μm was used as the raw material nonwoven fabric. An opening was formed in this spunbonded nonwoven fabric using a circular needle having a diameter of 3 mm.

[Comparative Example 2]
Implemented except that the same raw material nonwoven fabric as in Example 1 was used, the transport speed of the nonwoven fabric on the outfeed roller 7 was 50 m / min, and the peripheral speed V1 at the top of the convex portion of the uneven roller was 34 m / min. A nonwoven fabric of Comparative Example 2 was produced under the same conditions as in Example 1. As in Example 1, the strain rate was determined using the above-described formulas (2), (3), and (4) and shown in Table 1. Further, similarly to Example 1, the draw ratio (V2 / V1) was obtained and shown in Table 1.

[Performance evaluation]
About the nonwoven fabric of Examples 1-6 and Comparative Examples 1-2, according to the method mentioned above, bulk softness, the number of the tearing parts 4, the tearing part 4 (the 1st arc-shaped tearing part 41, the 2nd arc-shaped tearing part 42, and circular shape) The ratio of the first arc-shaped tear portion 41 in the tear portion 43) and the air permeability were measured. The evaluation environment was a room temperature of 20 ° C. and a humidity of 60% RH. The results are shown in Table 1 below.

  Moreover, the surface sheet is removed from the product of “Mary's (registered trademark) Mary's pants” manufactured by Kao Corporation, and the nonwoven fabrics of Examples 1 to 6 and Comparative Examples 1 and 2 are used instead, and the fibers are raised. The disposable diaper which used the nonwoven fabric of Examples 1-6 and Comparative Examples 1-2 was produced so that the surface might be the side which contacts a wearer's skin side. And about the said diaper, according to the following method, the absorbability of the stool and the liquid return property were evaluated, respectively. The evaluation environment was a room temperature of 22 ° C. and a humidity of 65% RH. The results are shown in Table 1 below.

[Evaluation of fluid return of soft stool]
The waistline gathers and the leg gathers were removed from the disposable diapers using the nonwoven fabrics of Examples 1 to 6 and Comparative Examples 1 to 2, and were fixed horizontally with the topsheet side up in the unfolded state. Using a metering pump at a position 125 mm from the tip of the longitudinal side of the covering sheet covering the absorbent core of the diaper, a total amount of glycerin / water = 94/6 solution that is virtual soft stool 10 g was injected. One minute after the injection, an OHP sheet whose weight was measured in advance was placed, and a roller having a weight of 1.9 kg and a width of 60 mm was placed thereon, and the roller was rotated in the longitudinal direction of the diaper. Thereafter, the OPH sheet was removed and the weight was measured, and the difference from the initial weight was calculated as the amount of returned stool fluid. The average value of three times for each disposable diaper was rounded to the nearest whole number, and the absorption time was measured. The results are shown in Table 1 below.

As is clear from the results shown in Table 1, it was found that the nonwoven fabrics of Examples 1 to 6 had a good touch while ensuring high air permeability as compared with the nonwoven fabrics of Comparative Examples 1 and 2. Moreover, it turned out that the disposable diaper using the nonwoven fabric of Examples 1-6 has high absorptivity of a soft stool compared with the disposable diaper using the nonwoven fabric of Comparative Examples 1-2, and it is hard to reverse a liquid. From the processing conditions of the nonwoven fabrics of Examples 1 to 6 and the processing conditions of the nonwoven fabric of Comparative Example 2, if the raw material nonwoven fabric is stretched at a strain rate of 1 × 10 ² s ⁻¹ or more, a nonwoven fabric having a tear portion is obtained. I found out. Further, from the processing conditions of the nonwoven fabric of Example 1 and the processing conditions of the nonwoven fabric of Example 2, the processing conditions of the nonwoven fabric of Example 5 and the processing conditions of the nonwoven fabric of Example 6, the number of tear parts of the obtained nonwoven fabric is as follows: It was found that there was a tendency to increase due to the strain rate rather than the draw ratio. Moreover, from the processing conditions of the nonwoven fabric of Example 3 and the processing conditions of the nonwoven fabric of Example 4, when the strain rate is the same speed, the number of tear portions of the resulting nonwoven fabric increases as the draw ratio increases. It turns out that there is a tendency.

DESCRIPTION OF SYMBOLS 1 Nonwoven fabric 2 Long fiber 20 Raised fiber 20a End part of raised fiber 20b Free end part of raised fiber 21 Fiber with which free end part 20b is thick 22 Fiber with which free end part 20b is not thick 23 Loop fiber 3 Heat Fusion part 4 Tear part 40 Opening part 41 1st arc-shaped tear part 42 2nd arc-shaped tear part 43 Circular tear part 200 Manufacturing apparatus 10, 10 'Raw material nonwoven fabric 10R Original fabric roll 5 Partial stretch processing part 51, 52 A pair of unevenness | corrugation Roller 511, 521 Convex part 512, 522 Concave part 53 Steel matching embossed roller 54, 55 Conveying roller 6 Brushed part 61 Convex roller 611 Convex part 62, 63 Conveying roller 7 Outfeed roller 100 Pants type disposable diaper 8 Absorbent body 81 Absorption Body 82 Top sheet 83 Back sheet 84 Side cuff 85 Elasticity for forming side cuff Material 9 outer cover material 91 inner sheet 92 outer sheet 93 waist elastic member 94 leg elastic members 9a, 9b side edge 9d legs A rear section, B ventral, C crotch portion

Claims (11)

A non-woven fabric formed from a web containing long fibers,
A plurality of tearing portions formed by tearing the web;
A part of the plurality of tear portions is torn in an arc shape, and the outer peripheral edge of the arc-shaped tear portion is rolled upward or downward from the outer surface of the nonwoven fabric to form an opening. The non-woven fabric is a non-woven fabric formed by fixing the web with a heat-sealing part,
The first arc-shaped tearing portion that forms the opening is torn along a part of the circumference of the entire circumference of the heat-sealing portion, and the long fibers between the adjacent heat-sealing portions are further separated. The nonwoven fabric according to claim 1, wherein the nonwoven fabric is formed by tearing.   The plurality of tear portions were torn in a circular shape, a first arc-shaped tear portion that forms the opening, a second arc-shaped tear portion that was torn in an arc shape and the outer peripheral edge of the arc-shaped tear portion was not bent The nonwoven fabric according to claim 1 or 2, comprising a circular tear portion.   The nonwoven fabric according to claim 3, wherein a ratio of the first arc-shaped tear portion in the tear portion is 30% or more.   A part of said long fiber is fractured | ruptured, It has the raising fiber in which only one end part is fixed by the said heat-fusion part, and the other end part side is a free end part. The nonwoven fabric described in 1.   An absorbent article using the nonwoven fabric according to any one of claims 1 to 5 as a constituent member. A raw material nonwoven fabric in which a web containing long fibers is fixed by a heat-sealing part is supplied between a pair of concavo-convex rollers, and a method for producing a nonwoven fabric in which a plurality of portions of the nonwoven fabric are partially stretched,
In the partial stretching process, the raw material nonwoven fabric is stretched at a strain rate of 1 × 10 ² s ⁻¹ or more,
It has a plurality of tear parts formed by tearing a web containing long fibers,
A method of manufacturing a nonwoven fabric, wherein a part of the plurality of tear portions is torn in an arc shape and an outer peripheral edge of the arc-shaped tear portion is rolled to form an opening portion. In the pair of concave and convex rollers, one roller has a plurality of convex portions on the peripheral surface, and the other roller has a concave portion in which the convex portion enters the peripheral surface at a position corresponding to the convex portion of the one roller. Have
The draw ratio (V2 / V1) of the conveyance speed (V2) of the manufactured nonwoven fabric to the peripheral speed (V1) at the top of the convex portion of the one roller is 1.2 or more. Manufacturing method of non-woven fabric.   The manufacturing method of the nonwoven fabric of Claim 7 or 8 which uses the nonwoven fabric whose breaking elongation of the direction orthogonal to the orientation direction of the said long fiber in one said heat-fusion part is 45% or less as said raw material nonwoven fabric. .   The method for producing a nonwoven fabric according to any one of claims 7 to 9, wherein the partial stretching process is performed at a temperature of 50 ° C or lower.   The raw material nonwoven fabric before performing the said partial extending | stretching process, or the nonwoven fabric after performing this partial extending | stretching process, The raising process which raises the constituent fiber of this nonwoven fabric is given. Nonwoven fabric manufacturing method.

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