JP5514948B1 - Nonwoven fabric and method for producing the same - Google Patents

Abstract

Disclosed is a non-woven fabric that has a feeling of fullness even when the breaking strength is high, and has a further improved touch feeling when first touched.
A non-woven fabric 1 of the present invention is a non-woven fabric in which a web containing long fibers 2 is fixed by a heat fusion part 3. The nonwoven fabric 1 includes a fiber 20 in which a part of the long fiber 2 is broken and only one end portion 20 a is fixed by the heat fusion portion 3. In the nonwoven fabric 1, the part located between the heat fusion parts 3 and 3 adjacent to the orientation direction (Y direction) of the long fiber 2 has an elongation of 35% or more with respect to a tensile load of 1 cN / 1 mm. is there.
[Selection] Figure 2

Description

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

  For example, for absorbent articles such as disposable diapers, spunbonded nonwoven fabrics are frequently used because they are high in breaking strength, excellent in processing suitability, and economical. However, the spunbonded nonwoven fabric has a lack of plumpness due to its manufacturing method, and it has been difficult to improve the touch feeling at the moment of touch.

  The present applicant has previously proposed a non-woven fabric comprising fibers in which a part of a long fiber is broken, only one end is fixed by a heat-sealed portion, and the free end on the other end is thickened. (See Patent Document 1).

JP 2012-92475 A

  According to the nonwoven fabric described in Patent Document 1, although the breaking strength is high, the whole has a feeling of plumpness and the touch is improved. However, there was no disclosure about improving the touch feeling at the moment of touching.

  The present invention is a nonwoven fabric in which a web containing long fibers is fixed by a heat-sealing portion, and includes a fiber in which a part of the long fibers is broken and only one end portion is fixed by the heat-sealing portion. The portion located between the heat fusion portions adjacent to each other in the orientation direction of the long fibers provides a nonwoven fabric having an elongation of 35% or more with respect to a tensile load of 1 cN / 1 mm. .

In addition, the present invention provides a method for producing a nonwoven fabric in which a plurality of portions of the nonwoven fabric are partially stretched at a temperature of 50 ° C. or less, and the nonwoven fabric subjected to the partial stretching processing is subjected to raising processing for raising constituent fibers of the nonwoven fabric. The raising process is performed using a convex roller having a plurality of convex portions on a peripheral surface, and the convex roller has a random pattern in which at least one of the convex portions in the rotation axis direction and the circumferential direction. The convex roller provides a method for producing a nonwoven fabric in which the processing distance obtained by the following formula (1) is 350 mm or more.

According to the nonwoven fabric of the present invention, although the breaking strength is high, the whole has a plump feeling, and the touch feeling when touched first is improved.
In addition, according to the method for producing a nonwoven fabric of the present invention, it is possible to continuously produce a nonwoven fabric having an overall feeling of fluff and improved touch feeling when first touched even though the breaking strength is high. .

FIG. 1 is a perspective view showing an embodiment of the nonwoven fabric of the present invention. 2 is a cross-sectional view taken along the line II shown in FIG. FIG. 3 is an explanatory diagram for explaining a method of measuring the elongation of a portion located between adjacent heat-sealed portions. FIG. 4 is a schematic view showing a method for measuring the amount of raised fibers of the nonwoven fabric of the present invention. FIG. 5 is a schematic view showing a preferred production apparatus used in the method for producing a nonwoven fabric of the present invention. FIG. 6 is a schematic diagram showing a partially stretched portion provided in the manufacturing apparatus shown in FIG. 7 is an enlarged cross-sectional view of a main part of the partially stretched portion shown in FIG. FIG. 8 is an enlarged cross-sectional view of a main part when the first uneven roller and the second uneven roller of the partially extending portion shown in FIG. FIG. 9 shows a position d _{1/2 that} bisects the engagement depth d ₀ when the first uneven roller and the second uneven roller of the partially stretched portion shown in FIG. It is the plane sectional view which looked at the plane section. FIG. 10 is a schematic diagram showing a raised processing portion provided in the manufacturing apparatus shown in FIG. FIG. 11 is a diagram showing a random pattern of convex portions of the raised portion shown in FIG. FIG. 12 is an explanatory diagram for explaining a processing distance by the convex roller provided in the raised processing unit. FIG. 13 is a diagram for explaining an example of the 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. 14 is a cross-sectional view taken along line II-II in FIG. FIG. 15 is a diagram illustrating a situation in which sensory evaluation of touch is performed. FIG. 16 is a diagram illustrating a situation in which sensory evaluation of a touch feeling is performed.

Hereinafter, the nonwoven fabric of this invention is demonstrated, referring FIGS. 1-4 based on the preferable embodiment.
As shown in FIG. 1, the nonwoven fabric 1 of the present embodiment is a nonwoven fabric in which a web including long fibers 2 is fixed by a heat fusion part 3, and a part of the long fibers 2 is broken, and only one end 20 a. Is provided with a fiber 20 fixed by the heat-sealing part 3. The nonwoven fabric 1 will be described below with the longitudinal direction of the nonwoven fabric 1 as the Y direction and the width direction of the nonwoven fabric 1 as the X direction, as shown in FIG. Regarding the nonwoven fabric 1, the MD direction along the fiber orientation direction is determined as the longitudinal direction (Y direction) and the CD direction perpendicular 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 this embodiment will be described in detail. The non-woven fabric 1 is a spunbonded non-woven fabric 10 in which a web containing long fibers 2 is intermittently crimped or fused with each other by a heat-sealing portion 3 and fixed. It is formed based on. Hereinafter, this will be described as the original spunbond nonwoven fabric (raw material nonwoven fabric) 10. The raw material nonwoven fabric 10 is a nonwoven fabric before breaking a part of 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 nonwoven fabric 1 is inexpensive and can provide a good touch feeling, and the basis weight is preferably 5 g / m ² or more, and preferably 100 g / m ² or less from the viewpoint of processing suitability. 25 g / m ² or less, more preferably 5 g / m ² or more and 100 g / m ² or less, more preferably 5 g / m ² or more and 25 g / m ² or less.

  From the viewpoint of improving the touch feeling at the moment of touch, the non-woven fabric 1 has a 1 cN / 1 mm tensile portion located between the heat fusion portions 3 and 3 adjacent to each other in the orientation direction (Y direction) of the long fibers 2. The elongation is 35% or more with respect to the load, preferably 40% or more, more preferably 50% or more, and particularly preferably 60% or more. The elongation is preferably 200% or less, more preferably 150% or less, and particularly preferably 120% or less. Specifically, the elongation is 1 cN / 1 mm. The elongation is preferably 40% or more and 200% or less with respect to the tensile load, more preferably 50% or more and 150% or less, particularly 60% or more and 120% or less. Is preferred. Although the measuring method of elongation is shown below, it is an elongation between the heat fusion parts 3 of the nonwoven fabric 1 or the raw material nonwoven fabric 10. A plurality of fibers between the embosses fixed by embossing are usually intertwined with each other and are difficult to move when an external force is applied, but the nonwoven fabric 1 having an elongation of 35% or more is fixed by embossing. Since the entanglement of the plurality of fibers between the embosses has been loosened and it is in a state where it can be easily moved with a small external force, the softness and touch feeling when the nonwoven fabric 1 is touched with the hand are improved. To do. The elongation is measured by the following method.

[Measurement method of elongation of the portion located between the heat fusion portions 3 and 3 adjacent to each other in the Y direction]
Under a 22 ° C. and 65% RH environment, a rectangular measurement piece having a size of 5 mm in the X direction and 50 mm or more in the orientation direction (Y direction) is cut out from the nonwoven fabric 1 or the raw material nonwoven fabric 10. Two heat-sealing parts 3 and 3 adjacent in the Y direction in the central region of the cut out rectangular measuring piece are selected. Next, as shown in FIG. 3, the non-woven fabric in the region T sandwiched between the selected two heat fusion portions 3 and 3, in other words, the portion located between the selected heat fusion portions 3 and 3. In order to measure the elongation of the region T, the Y-direction of the region T extends from both side edges along the Y-direction of the rectangular measurement piece at an intermediate position in the Y-direction of the two heat-sealing portions 3 and 3. A measurement sample is prepared by making cuts extending in the X direction to the positions of both side edges. This measurement sample is attached to the chuck of a tensile tester (for example, Tensilon tensile tester “RTA-100” manufactured by Orientec Co., Ltd.) so that the Y direction is the tensile direction. The distance between chucks is 25 mm. The measurement sample is pulled at 50 mm / min, and the elongation (%) is measured when a tensile load of 1 cN / 1 mm is applied to a width of 1 mm. The elongation (%) is the ratio of the length increased by the extension to the set inter-chuck distance. For example, when a sample having the set inter-chuck distance of 25 mm is extended to 50 mm, The elongation (%) is {(50−25) / 25} × 100 = 100%.

  The nonwoven fabric 1 has a breaking strength value of preferably 5.00 N / 50 mm or more, more preferably 8 N / 50 mm or more and 30 N / 50 mm or less, from the viewpoint of prevention of breakage during use and processing suitability. preferable. The value of the breaking strength of the raw nonwoven fabric 10 is preferably 7 N / 50 mm or more, and more preferably 10 N / 50 mm or more and 50 N / 50 mm or less, from the viewpoint of achieving the breaking strength of the nonwoven fabric 1. Thus, the manufacturing method of the nonwoven fabric 1 mentioned later is a method with little fall from the value of the breaking strength of the raw material nonwoven fabric 10 compared with the other conventional raising method. It is preferable that the breaking strength of the nonwoven fabric 1 and the raw material nonwoven fabric 10 satisfies the above range in the X direction (CD direction). The ratio of the breaking strength between the nonwoven fabric 1 and the raw material nonwoven fabric 10 (breaking strength of the nonwoven fabric 1 / breaking strength of the raw material nonwoven fabric 10) is 0.5 or more, preferably 0.7 or more and 1.0 or less, more specifically. Is preferably 0.5 or more and 1.0 or less, and more preferably 0.7 or more and 1.0 or less. The breaking strength is measured by the following method.

[Measurement method of breaking strength]
Under a 22 ° C. and 65% RH environment, a rectangular measuring piece having a size of 200 mm in the X direction (width direction) and 50 mm in the Y direction (longitudinal direction) is cut out from the nonwoven fabric 1 or the raw material nonwoven fabric 10. The cut out rectangular measurement piece is used as a measurement sample. 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 X direction is the tensile direction. The distance between chucks is 150 mm. The measurement sample is pulled at 300 mm / min, and the maximum load point until the sample breaks is defined as the breaking strength in the X direction. Further, a rectangular measurement piece having a size of 200 mm in the Y direction and 50 mm in the X direction is cut out and used as a measurement sample. This measurement sample is attached to the chuck of a tensile tester so that the Y direction is the tensile direction. The breaking strength in the Y direction is obtained by the same procedure as the method for measuring the breaking strength in the X direction described above.

The nonwoven fabric 1 has a bulk softness of preferably 4.5 cN or less, more preferably 3 cN or less, still more preferably 2.5 cN or less, and more preferably 0.1 cN or more from the viewpoint of excellent bulk softness. It is preferable that it is 0.5 cN or more. Specifically, it is preferably 0.1 cN or more and 4.5 cN or less, more preferably 0.1 cN or more and 3 cN or less, in terms of becoming supple, such as a baby or infant. More preferably, it is 5 cN or more and 2.5 cN or less.
The raw nonwoven fabric 10 has a bulk softness of preferably 10 cN or less, more preferably 6 cN or less, and more preferably 1 cN or more from the viewpoint of obtaining a soft and soft feel. Specifically, it is preferably 0.5 cN or more and 10 cN or less, and more preferably 1 cN or more and 8 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.

The nonwoven fabric 1 has a compression characteristic value at the time of a minute load of 14.7 (cN / cm ² ) / mm (15 (gf / cm ² ) / mm) or less from the viewpoint of providing a soft feeling. Is preferably 11.8 (cN / cm ² ) / mm (12 (gf / cm ² ) / mm) or less, more preferably 10.8 (cN / cm ² ) / mm (11 (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 1.0 (cN / cm ² ) / mm (1.0 (gf / cm ² ) / mm) from the viewpoint of production. By the way, the compression characteristic value of the raw material nonwoven fabric 10 having a basis weight of about 5 to 25 g / m ² that has not been processed is 19.6 (cN / cm ² ) / mm (20.0 (gf / cm ² ). / Mm) to 29.4 (cN / cm ² ) / mm (30.0 (gf / cm ² ) / mm). The compression characteristic value at the time of a minute load is measured by the method described in JP2012-92475A. This will be specifically described below.

[Measurement method of 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 rate is 20 μm / sec, the maximum compression load is 9.80 cN / cm ² (10.0 gf / cm ² ), and the recovery process is also measured at the same rate. At this time, the amount of displacement between the steel plates is x (mm), the load is y (cN / cm ² ), and the position of the point where the load is detected is 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 that is not a recovery process is a load between 0.29 cN / cm ² (0.30 gf / cm ² ) and 0.98 cN / cm ² (1.00 gf / cm ² ), and at that time The amount of deformation data is extracted, an approximate straight line is obtained for the relationship between x and y by the least square method, and the slope at that time is defined as the characteristic value (unit (cN / 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. The compression characteristic value at the time of a minute load indicates that the lower the numerical value, the easier it is to be crushed with a smaller load, and it is possible to express the good feeling (particularly plump feeling) when the nonwoven fabric is rubbed.

  In the nonwoven fabric 1, the raised fiber including the fiber 20 in which only one end 20a is fixed by the heat-sealing part 3 is 10 / cm or more from the viewpoint of improving the touch. Preferably, the number is 15 / cm or more. From the viewpoint of obtaining sufficient breaking strength, the upper limit is preferably 50 pieces / cm or less. Here, the “raised fiber” means a loop between the fiber 20 in which only one end portion 20 a is fixed by the heat fusion part 3 and the heat fusion parts 3, 3 in the nonwoven fabric 1. The fiber which consists of the loop-shaped fiber 21 standing up in the shape is meant. The amount of the raised fiber is measured by the following measuring method. As shown in FIG. 2, the loop-shaped fiber 21 means a fiber that does not have a free end portion and is fixed at both ends by the heat-sealing portion 3.

[Measurement of the amount of raised fibers]
FIG. 4 is a schematic view showing a method for measuring the amount of fibers raised in the fibers constituting the nonwoven fabric 1 in an environment of 22 ° C. and 65% RH. First, from a non-woven fabric to be measured, a 20 cm × 20 cm measuring piece is cut out with a sharp razor, and as shown in FIG. 4A, X passes through a plurality of heat-sealed portions 3 on the raised surface of the measuring piece. A measurement sample 104 is formed by folding in a fold line Z extending in the direction. Next, this measurement sample 104 is placed on an A4 size black mount, and as shown in FIG. 4B, an A4 size black mount in which holes 107 of 1 cm in length and 1 cm in width are further formed. Put on. At this time, as shown in FIG. 4B, the fold 105 of the measurement sample 104 is arranged so that it can be seen from the hole 107 of the upper black mount. For both mounts, “Kenran (black) continuous weight 265 g” of Fuji Kyowa Paper Co., Ltd. was used. Thereafter, a weight of 50 g is placed on each side of the upper mount hole 107 at a position 5 cm outward along the fold line 105 to create a state in which the measurement sample 104 is completely folded. Next, as shown in FIG. 4C, the inside of the hole 107 of the mount is observed at a magnification of 30 using a microscope (VHX-900 manufactured by KEYENCE), and the measurement sample 104 has a fold 105 to 0. Measure the number of raised fibers per 1 cm raised above the imaginary line 108 formed at the position translated parallel by 2 mm. Nine points are measured, and the average value (rounded to the second decimal place) is taken as the amount of raised fibers.

  Further, when counting the number of raised fibers, for example, there is a fiber that crosses the virtual line 108 that is 0.2 mm above the fold 105 twice, such as a fiber 106a shown in FIG. The fiber counts as two. Specifically, in the example shown in FIG. 4C, there are four fibers crossing the virtual line 108 once and one fiber 106a crossing the virtual line 108 twice, but two fibers 106a crossing the virtual line 108 twice. Counted as a book, the amount of raised fibers is 6 / cm.

  Further, the raised fibers preferably have a height of 0.7 mm or more, and more preferably 2.0 mm or more, from the viewpoint of enhancing the feeling of plumpness and enhancing the touch feeling. When the height of the raised fiber exceeds 5 mm, the appearance becomes fluffy, and when it is rubbed during use, it becomes fluffy or fluffy. From this viewpoint, the height of the raised fiber is preferably 5 mm or less, and more preferably 3 mm or less. Here, the height of the raised fiber means the fiber height in a natural state without pulling the fiber during measurement, unlike the length of the fiber. When the value of the length of the raised fiber is large or the rigidity of the fiber is high, the height of the raised fiber tends to increase. The height of the raised fiber is measured by the following measurement method.

  The height of the raised fiber is measured simultaneously when the amount of the raised fiber is measured. Specifically, as shown in FIG. 4C, the inside of the hole 107 of the mount is observed, and a line is drawn in parallel from the crease 105 to a point where fibers that are raised every 0.05 mm do not intersect. Next, compared to the amount of raised fibers measured as described above (determined from the imaginary line 108 above 0.2 mm), a parallel line that halves the fibers that intersect the parallel line is selected, and from there Measure the distance to the crease. Three sheets are measured for the nonwoven fabric for measuring the above operation, and an average of nine places in three places and three pieces per piece is taken as the height of the raised fiber.

The heat-sealed portion 3 by embossing shown in FIGS. 1 and 2 preferably has an area of each heat-fused portion 3 of 0.05 mm ² or more and 10 mm ² or less from the viewpoint of touch and suitability for processing. and more preferably 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 thermocompression bonding is preferable in that the fiber is easily broken. The shape of the heat fusion part 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 area of the heat fusion part 3 to the surface area of one surface of the nonwoven fabric 1 is preferably 5% or more and 30% or less, and it is 10% or more and 20% or less because it is difficult to produce pills. Further preferred.

  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 roughly divided into a partially stretched portion 4 and a raised portion 5 disposed on the downstream side of the partially stretched portion 4.

  The partially stretched portion 4 is a portion that performs a partially stretched process on each of a plurality of portions of the nonwoven fabric 10. In the manufacturing apparatus 200 of the present embodiment, a pair that partially stretches the nonwoven fabric 10 as shown in FIGS. The first uneven roller (first type) 41 and the second uneven roller (second type) 42 are provided. The “partial stretching” process referred to here is a method of processing so as to have an unstretched part and a stretched part instead of subjecting the entire nonwoven fabric to a stretching process due to a difference in speed between rollers. . The unstretched portion is a portion of the nonwoven fabric that has not been stretched, and “do not stretch” means that the stretch treatment is not actively applied.

  As shown in FIG. 6, the first uneven roller 41 is adjacent to a plurality of convex portions 411 regularly arranged in the transport direction (Y direction) and the width direction (X direction) in the transport direction (Y direction). It has the some convex part 411 and the some recessed part 412 distribute | arranged between the convex parts 411 adjacent in the width direction (X direction). Similarly to the first concavo-convex roller 41, the second concavo-convex roller 42 also has a plurality of convex portions 421 regularly arranged in the transport direction (Y direction) and the width direction (X direction), and the transport direction (Y direction). And the plurality of concave portions 422 arranged between the convex portions 421 adjacent to each other in the width direction (X direction). In the manufacturing apparatus 200, as shown in FIG. 6, in order to transport the nonwoven fabric 10 in the transport direction (Y direction), the concave and convex rollers 41 and 42 are rotated in the circumferential direction. The convex portions 411 and the plurality of convex portions 421 of the second concave-convex roller 42 are respectively disposed on the peripheral surfaces of the concave-convex rollers 41, 42, and are uniform in the circumferential direction and the rotation axis direction (X direction). Arranged regularly. Further, the convex portion 411 of the first concave / convex roller 41 is disposed at a position corresponding to the concave portion 422 of the second concave / convex roller 42, and the convex portion 421 of the second concave / convex roller 42 corresponds to the concave portion 412 of the first concave / convex roller 41. It is arranged in. That is, the convex portion 411 of the first concave / convex roller 41 enters the concave portion 422 of the second concave / convex roller 42, and the convex portion 421 of the second concave / convex roller 42 enters the concave portion 412 of the first concave / convex roller 41. The pair of first concavo-convex rollers 41 and second concavo-convex rollers 42 provided with such convex portions 411 and 421 and concave portions 412 and 422 are so-called steel matching emboss rollers.

The top shapes of the convex portions 411 of the first concave / convex roller 41 and the convex portions 421 of the second concave / convex roller 22 are circular, quadrangular (diamond, rectangular, etc.), elliptical, polygonal (hexagon, eight (Square, dodecagon, dodecagon, etc.). The area of the top surface of the convex portions 411 and 421 is preferably 1 mm ² or more and 100 mm ² or less from the viewpoint of improving the softness of the nonwoven fabric 4 after processing while preventing penetration during processing of the nonwoven fabric 4. and more preferably ² or more 25 mm ² or less. It edge portion of the top of the convex portions 411 and 421 is R-shaped, preferably from the viewpoint of nonwoven fabric pores is less likely to open at the time of processing, 0.2 mm or more 0.5mm or less × dots long as R value A ₁ (Distance in the circumferential direction of the top of the convex portions 411, 421) or 0.2 mm to 0.5 mm × dot length A ₂ (distance in the X direction of the top of the convex portions 411, 421) 7). In this case, the area of the top surface of the convex portions 411 and 421 is an R intermediate point (projecting the convex portion from the upper surface). The partial mechanical stretch ratio described later is similarly determined from the midpoint.

  Further, the shape of the convex portions 411 and 421 viewed from the side includes a trapezoidal shape, a quadrangular shape, a curved shape or the like as shown in FIG. From the viewpoint of forming a gap between the convex and concave portions 421 of the second uneven roller 42, a trapezoid or a rectangle is preferable, and an average elevation angle (base angle) α (see FIG. 8) of the trapezoid is preferably 77 ° or more. In forming the gap, it is more preferably 85 ° or more and 150 ° or less.

The convex portions 411 of the first uneven roller 41 are uniform, and the height h ₁ (see FIG. 8) from the peripheral surface of the roller 41 to the apex of the convex portion 411 is preferably 1 to 10 mm. More preferably, it is ˜7 mm. The distance (pitch) between the convex portions 411 adjacent to each other in the rotation axis direction (X 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 projections adjacent in the circumferential direction. The distance between the portions 411 (pitch P ₁ (see FIG. 8)) is preferably 0.01 mm or more and 20 mm or less, and more preferably 1 mm or more and 10 mm or less. The same applies to the convex portions 421 of the second uneven roller 42. Note that the heights of the convex portions 411 of the first concave / convex roller 41 and the convex portions 421 of the second concave / convex roller 42 are not the same if the pitch in the X direction and the pitch in the circumferential direction are the same. May be. In the manufacturing apparatus 200, as shown in FIG. 8, the height h ₁ of the convex portion 411 of the first concave / convex roller 41 and the height h ₂ of the convex portion 421 of the second concave / convex roller 42 are different from each other. The convex portion 421 of the concave / convex roller 42 is formed higher than the convex portion 411 of the first concave / convex roller 41.

The top shapes of the convex portions 411 of the first concave / convex roller 41 and the convex portions 421 of the second concave / convex roller 42, and the bottom shapes of the concave portions 412 of the first concave / convex roller 41 and the concave portions 422 of the second concave / convex roller 42, respectively. May be the same or different, but from the viewpoint of forming a gap (gap between the convex portion 411 of the first concave-convex roller 41 and the convex portion 421 of the second concave-convex roller 42) during roller rotation , May be different. Specifically, it is preferable that the area of the bottom surface of the concave portions 412 and 422 is larger than the area of the top surface of the convex portions 411 and 421, and the area of the bottom surface of the concave portions 412 and 422 is 4 mm ² or more and 225 mm ² or less. Preferably, it is 4 mm ² or more and 36 mm ² or less.
The area ratio of the area of the top of the concavo-convex roller (ratio of the area of the top to the total area of the concavo-convex processed area) is 4% to 20%, more preferably 7% to 15% for both the first roller and the second roller. When it is below, the non-woven fabric cannot be formed into a narrow pressure part, and the touch is good and a stretch ratio is high (the stretch ratio increases as the area ratio decreases).

Hereinafter, the case where the first uneven roller 41 and the second uneven roller 42 are meshed to the maximum will be described. Here, “when fully meshed” is not meshing during processing when the nonwoven fabric 10 is partially stretched through the nonwoven fabric 10 between the pair of first uneven rollers 41 and the second uneven rollers 42. This means a state when the first uneven roller 41 and the second uneven roller 42 are forcibly meshed without passing through the nonwoven fabric 10. Specifically, the tops of at least one of the convex portions 411 and 421 of the first concave and convex rollers 41 and 42 are brought into contact with the bottom surfaces of the other concave portions 422 and 412, and the first concave and convex rollers 41 and the second concave and convex rollers 42. when mated to maximize, that is, for example, in the manufacturing apparatus 200, as described above, higher height h ₂ of the convex portion 421 of the second uneven roller 42 than the height h ₁ of the first recess-projection roller 41 Therefore, when the top of the convex portion 421 of the second concave-convex roller 42 is abutted against the bottom surface of the concave portion 412 of the first concave-convex roller 41, the first concave-convex roller 41 and the second concave-convex roller 42 are bitten to the maximum. It is when they are put together.

As shown in FIG. 8, when the first concave / convex roller 41 and the second concave / convex roller 42 are engaged with each other to the maximum, a cross-sectional view at a position d _{1/2 that} bisects the engagement depth d ₀ ( The convex portions 411 and 421 engaged with the first concave _/ convex roller 41 and the second concave / convex roller 42 were cut in the parallel direction along the width direction (X direction) at the bisecting position d1 _/ 2. 9), a gap of 0.1 mm or more and 10 mm or less is formed over the entire circumference of the convex portions 411 and 421 of each of the first concave and convex rollers 41 and 42 as shown in FIG. From the viewpoint of improving the feel of the nonwoven fabric 10 and maintaining strength, the gap over the entire circumference is preferably 0.6 mm or more and 8 mm or less, and more preferably 0.8 mm or more and 3 mm or less. preferable. Here, “a gap is formed over the entire circumference of the convex portions 411 and 421” means that there is a gap between the convex portion 411 adjacent to the Y direction and the convex portion 421 as shown in FIG. It is formed, and a gap is also formed between the convex part 411 and the convex part 421 adjacent in the X direction, which means that the convex part 411 and the convex part 421 are completely separated and independent. . The gap is a measured value at the narrowest position on the entire circumference. At this time, the meshed state is adjusted so that the difference between the maximum gap and the minimum gap is minimized.

Further, as shown in FIG. 8, the pressing amount (meshing depth) when the first concavo-convex roller 41 and the second concavo-convex roller 42 are maximally engaged is 3 from the viewpoint of improving the touch of the nonwoven fabric 10 after processing. It is preferably 5 mm or more, more preferably 4 mm or more and 10 mm or less, and particularly preferably 4 mm or more and 6 mm or less. Here, “the amount of pressing when fully engaged” means that the convex portion 411 of the first concave / convex roller 41 and the convex portion 421 of the second concave / convex roller 42 adjacent to the convex portion 411 are meshed to the maximum. This means the same as the depth d ₀ of the meshing.

Further, the first concavo-convex roller 41 and the second concavo-convex roller 42 are meshed to the maximum, and as shown in FIG. 8, the engagement of the first concavo-convex roller 41 and the second concavo-convex roller 42 is viewed in a longitudinal section (first concavo-convex roller 41 And the second concave-convex roller 42 are cut in the vertical direction (thickness direction) along the transport direction (Y direction), and the meshing depth d ₀ is bisected. The ratio of the gap in the transport direction obtained using the following formula (2) at the position d _1/2 is preferably 2% or more and less than 60% from the viewpoint of improving the touch of the nonwoven fabric 4 and maintaining the strength. 10 to 40% is more preferable.

Ratio of gap in conveyance direction = {[(a− (b + c)] / a} × 100 (2)

Here, a is the position of the convex portions 411, 421 of one of the first concave / convex rollers 41 and the second concave / convex rollers 42 adjacent to each other in the conveying direction (Y direction) at the position d1 _/ 2. pitch, b is two thickness equal to the position d _1/2 one in the conveying direction of the convex portions 411 and 421 of the recess-projection roller in (Y-direction), c is the other at position d _1/2 bisecting It is the thickness in the conveyance direction (Y direction) of the convex portions 421 and 411 of the concave and convex rollers. For example, using the manufacturing apparatus 200 shown in FIG. 8, a is the pitch of the convex portions 421 of the second concave and convex rollers 42 adjacent to each other in the circumferential direction at the position d _1/2 that bisects, and b is bisected. The thickness of the convex portion 421 of the second concave _/ convex roller 42 in the conveyance direction at the position d _1/2 to be moved, and c is the thickness of the convex portion 421 of the first concave _/ convex roller 41 in the conveyance direction at the position d _1/2 to bisect. It is.

Furthermore, from the viewpoint of improving the feel of the nonwoven fabric 10 after processing and maintaining the strength, when the first uneven roller 41 and the second uneven roller 42 are meshed to the maximum, the top of the convex portion 411 of the first uneven roller 41 and There is a gap of 0.2 mm or more between the bottom surface of the concave portion 422 of the second concave / convex roller 42 or between the top portion of the convex portion 421 of the second concave / convex roller 42 and the bottom surface of the concave portion 412 of the first concave / convex roller 41. It is more preferable that there is a gap of 0.2 mm or more and 10 mm or less. For example, in the manufacturing apparatus 200, as described above, the height h ₂ of the convex portion 421 of the second uneven roller 42 is formed higher than the height h ₁ of the first concave-convex roller 41, the first concave-convex roller The aforementioned predetermined gap is formed between the top of the convex portion 421 of 41 and the bottom surface of the concave portion 422 of the second uneven roller 42.

  The pair of first concavo-convex rollers 41 and the second concavo-convex rollers 42 rotate when a driving force from a driving means (not shown) is transmitted using a gear (not shown). The pair of first concavo-convex rollers 41 and the second concavo-convex rollers 42 may be rotated by meshing with one of the rotating shafts by transmitting a driving force from a driving means (not shown). From the viewpoint of effective partial stretching by stretching at the center of the groove, it is preferable to transmit driving force using gears to both rotating shafts, apart from meshing. The rotational speeds (circumferential speed V) of the pair of first uneven rollers 41 and the second uneven rollers 42 are controlled by a control unit (not shown) included in the manufacturing apparatus 200. Here, the circumferential speed V of the first concavo-convex roller 41 and the second concavo-convex roller 42 is substantially the same as the speed on the surface of the first concavo-convex roller 41, and more specifically, the convexity of the first concavo-convex roller 41. The position obtained by subtracting the engagement depth D at the time of processing, which will be described later, from the top end of the portion 411 is used as the diameter, and is obtained as the circumferential speed from the rotational speed of the roller.

  As shown in FIG. 10, the raised processing portion 5 includes a convex roller 51 having a plurality of convex portions 511 on the peripheral surface. The convex roller 51 is of a metallic cylindrical shape such as an aluminum alloy or steel. The convex roller 51 rotates when a driving force from a driving means (not shown) is transmitted to its rotating shaft. The rotation speed of the convex roller 51 is controlled by a control unit (not shown) included in the manufacturing apparatus. As shown in FIG. 10, the raised processing unit 5 includes transport rollers 52 and 53 that transport the partially stretched nonwoven fabric 10 ′ on the upstream side and the downstream side of the convex roller 51. The conveyance speed of the stretched nonwoven fabric 10 ′ is controlled by a control unit (not shown) provided in the manufacturing apparatus.

The convex roller 51 cannot be expressed in a regular repeating pattern in at least one of the convex and concave shapes formed by the convex portions 511 and the concave portions 512 when measured in the rotation axis direction (X direction) and the circumferential direction of the convex roller 51. And has an uneven shape composed of random patterns. An example of the random pattern is represented by a roughness curve as shown in FIG. When the scanning direction of the roughness curve is the X axis, the amplitude direction is the Y axis, and the roughness curve is expressed as Y = f (X), the random pattern is the roughness curve Y = f (X) as a frequency. It means that it cannot be expressed as a combination of periodic functions when analyzed.
The roughness curve was measured using a contact-type roughness meter “SURFTEST SJ-210 (manufactured by Mitutoyo Corporation)”.
Since the convex portion 511 of the convex roller 51 has a random pattern in the circumferential direction of the convex roller 51, the convex portion having a different height enters the nonwoven fabric 10 ′ at a random depth and scratches the fibers in the nonwoven fabric 10 ′. The long fibers in the nonwoven fabric 10 ′ are scratched at random positions in the thickness direction in the nonwoven fabric 10 ′, and a part thereof is broken. By scratching the long fibers in the nonwoven fabric 10 ′ at random positions in the thickness direction in the nonwoven fabric 10 ′, the bundled long fibers in the nonwoven fabric are randomly loosened in the thickness direction of the nonwoven fabric, and the touch feeling is greatly improved. When the convex portion 511 enters the nonwoven fabric 10 ′ at a uniform depth and scratches the long fibers in the nonwoven fabric 10 ′, if the convex portion 511 is shallow, only the surface layer in the nonwoven fabric 10 ′ is loosened, and the touch feeling is improved. In addition, when the protrusion 511 is deeply penetrated, the whole of the nonwoven fabric 10 'is loosened, but the long fibers 2 are also ruptured and broken, and the touch feeling is not improved.
Furthermore, when the convex part 511 of the convex roller 51 is also random in the rotation axis direction of the convex roller 51, the random pattern improves the touch more uniformly in the X direction (width direction) of the nonwoven fabric 10 ′. There is also an advantage of being able to.

In the convex roller 51, the processing distance obtained by the following formula (1) is preferably 350 mm or more, more preferably 800 mm or more, and particularly preferably 1000 mm or more. It is preferably 10,000 mm or less, more preferably 5000 mm or less, specifically preferably 350 mm or more and 10,000 mm or less, and more preferably 1000 mm or more and 5000 mm or less.
In addition, the processing distance calculated | required by following formula (1) means the distance which the convex roller 51 and the nonwoven fabric contact | connect as shown in FIG. Further, the roller diameter of the convex roller 51 indicated by D is the diameter on the peripheral surface of the convex roller 51.

  Next, one embodiment of the method for producing a nonwoven fabric of the present invention will be described with reference to FIG.

In the method for producing a nonwoven fabric of the present invention, a raw material nonwoven fabric 10 is used as a raw material for the nonwoven fabric 1. Examples of the raw material nonwoven fabric 10 include a spunbond nonwoven fabric and a laminated nonwoven fabric of a spunbond layer and a meltblown layer. Examples of the laminated nonwoven fabric include a spunbond-spunbond laminated nonwoven fabric and a spunbond-spunbond-spun layer. Bond laminated nonwoven fabric, spunbond-meltblown-spunbond laminated nonwoven fabric, spunbond-spunbond-meltblown-spunbond laminated nonwoven fabric, and the like. When the spunbond nonwoven fabric or the laminated nonwoven fabric is used, the constituent fibers constituting the nonwoven fabric are made of a thermoplastic resin, and the thermoplastic resins include polyolefin resins, polyester resins, polyamide resins, acrylonitrile resins, vinyl resins. And vinylidene resins. 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. Modified products and mixtures of these various resins can also be used. Among thermoplastic resins, polyolefin resins are particularly preferably used from the viewpoints of cost and touch. From the same viewpoint, the fineness of the constituent fibers is preferably 0.5 dtex or more and 5 dtex or less, and more preferably 1 dtex or more and 3 dtex or less. The basis weight of the raw material nonwoven fabric 10 is preferably 5 g / m ² or more and 50 g / m ² or less, and more preferably 8 g / m ² or more and 25 g / m ² or less. A plurality of heat Chakubu by embossing for forming the raw nonwoven fabric 10, the area of each heat fusion portion, it is preferably 0.05 mm ² or more 10 mm ² or less, 0.1 mm ² or more 1 mm ² or less More preferably. The number of the heat-sealed portions is preferably 10 pieces / cm ² or more and 250 pieces / cm ² or less, and more preferably 35 pieces / cm ² or more and 65 pieces / cm ² or less. The shape of the heat fusion part is not particularly limited, and may be any shape such as a circle, a rhombus, and a triangle. The ratio of the total area of the heat-sealed portion to the surface area of one surface of the raw material nonwoven fabric 10 is preferably 3% to 50%, and more preferably 5% to 30%.

Note that a small amount of additives such as an antistatic property agent, a lubricant, and a hydrophilic agent may be added to the fibers constituting the raw material nonwoven fabric 10.
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.

  In the method for producing a nonwoven fabric of the present invention, first, partial stretching is performed on each of a plurality of locations of the raw material nonwoven fabric 10 at a temperature of 50 ° C. or lower. Specifically, first, the belt-shaped raw material nonwoven fabric 10 is unwound from a raw roll (not shown), and the raw material nonwoven fabric 10 is steel-matched embossed roller via conveying rollers 44 and 45 as shown in FIG. The raw material nonwoven fabric 10 is partially stretched by being conveyed between a pair of rollers 41 and 42. More specifically, the conveyed raw material nonwoven fabric 10 is moved between a plurality of convex portions 411 of one roller 41 and a plurality of concave portions 422 of the other roller 42 shown in FIGS. 6 and 7. Further, the pressing force is further applied between the plurality of convex portions 421 of the other roller 42 and the plurality of concave portions 412 of the one roller 41, so that the conveying direction and the conveying direction are respectively applied to a plurality of locations of the raw material nonwoven fabric 10. Stretching is performed in a direction perpendicular to In this way, by performing stretching in the transport direction and the direction orthogonal to the transport direction, it is possible to suppress the decrease in breaking strength of the manufactured nonwoven fabric 1 by direction. The temperature of 50 ° C. or lower means that the temperature is not normal when the rollers 41 and 42 are not actively heated and the raw nonwoven fabric 10 is stretched. In other words, when the raw nonwoven fabric 10 is stretched, the melting point of any kind of constituent fiber resin from the viewpoint that the raw nonwoven fabric 10 does not become hard by causing heat fusion between the constituent fibers of the nonwoven fabric. Means a lower temperature. In addition, the direction orthogonal to the conveyance direction is the same direction as the rotation axis direction of the roller described above.

  Next, raising process which raises the constituent fiber of raw material nonwoven fabric 10 is given to raw material nonwoven fabric 10 'to which partial extension processing was given. Specifically, the raw material nonwoven fabric 10 'is conveyed to the convex roller 51 via the conveying rollers 52 and 53 as shown in FIG. In the raising process part 5, using the convex roller 51 which has the convex part 511 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 comprises the raw material nonwoven fabric 10. The nonwoven fabric 1 having the fibers 20 fixed by the heat fusion part 3 is continuously manufactured (see FIGS. 1 and 2). From the viewpoint of breaking a part of the long fiber 2 and efficiently forming the fiber 20 shown in FIG. 1, it is preferable to rotate the rotation direction of the convex roller 51 in the direction opposite to the conveying direction of the raw material nonwoven fabric 10 ′. The convex roller 51 is preferably rotated at a speed not less than 0.3 times and not more than 10 times the conveying speed of the raw material nonwoven fabric 10 ′. When rotating in the circumferential direction (forward direction with respect to the transport direction), it is preferable to rotate the convex roller 51 at a speed of 1.5 times or more and 20 times or less. Here, the speed of the convex roller 51 means the peripheral speed on the peripheral surface of the convex roller 51.

  In addition, when forming the fiber 20 in which only one end portion 20a is fixed by the heat-sealing portion 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 51. Is further processed by another convex roller 51.

  Since the nonwoven fabric manufactured by the suitable manufacturing method of the nonwoven fabric 1 mentioned above forms the weakening point in the heat-fusion part 3 with the steel matching embossing roller 43, and raises with the convex roller 51, it is manufactured with the conventional raising method. It is characterized in that the proportion of the loop-like fibers 21 is smaller than that of the non-woven fabric. Further, since the weakening point is formed in the heat-bonding portion 3 by the steel matching embossing roller 43 and the raised roller 51 is raised, so-called breaks (fissures, holes) are hardly formed between the heat-bonding portions 3, and the raw material nonwoven fabric 10 The breaking strength of can be maintained as it is.

The effect at the time of using the nonwoven fabric 1 of embodiment of this invention mentioned above is demonstrated.
In the nonwoven fabric 1 of this embodiment, as shown in FIG.1 and FIG.2, the fiber 20 by which a part of long fiber 2 is fractured | ruptured and only the one end part 20a is being fixed by the heat-fusion part 3 is formed. ing. Moreover, in the nonwoven fabric 1, the part (refer FIG. 3) located between the heat-fusion parts 3 and 3 adjacent to the orientation direction (Y direction) of the long fiber 2 is with respect to the tensile load of 1 cN / 1mm. The elongation is 40% or more. Therefore, despite the high breaking strength, there is a feeling of plumpness as a whole, and the touch feeling when touched first is further improved. The spunbond nonwoven fabric or the spunbond laminated nonwoven fabric used as the raw material nonwoven fabric 10 has less plumpness in the past and is inferior to the touch compared to the nonwoven fabric of the air-through manufacturing method. Smoothness and plumpness have been added to greatly improve the touch.
Moreover, according to the manufacturing method of the nonwoven fabric 1 of this embodiment, although the breaking strength is high as described above, the nonwoven fabric 1 has an overall plump feeling and further improved the touch feeling when first touched. Can be manufactured 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. Hereinafter, the disposable diaper using the nonwoven fabric 1 will be described as an example.

As shown in FIGS. 13 and 14, the pants-type disposable diaper 100 is positioned on the non-skin contact surface side of the absorbent main body 50 including the absorbent body 40 and fixes the absorbent main body 50. The outer packaging material 60 is provided.
As shown in FIG. 14, the absorbent main body 50 includes a liquid-permeable top sheet 70, a liquid-impermeable (including water-repellent) back sheet 80, and a liquid-retaining property interposed between both sheets 70 and 80. It has the absorber 40 and is substantially vertically long as shown in FIG.
As shown in FIG. 13, the outer packaging material 60 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 6a and 6b 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). Further, the outer packaging material 60 includes an outer layer sheet 62 that forms the outer surface of the diaper, and an inner layer sheet 61 that is located on the skin contact surface side and is partially joined to the outer layer sheet 62. The waist elastic member 63 and the leg elastic member 64 for gathering are disposed between the sheets 61 and 62 in the waist and leg 6d that form the leg opening.

As shown in FIG. 13, the absorbent main body 50 is disposed across the back side portion A and the abdominal side portion B of the outer packaging material 60, and both end portions in the longitudinal direction of the absorbent main body 50 are disposed on the outer packaging material 60. It is in the position retreated inward in the longitudinal direction from both ends in the longitudinal direction. As shown in FIG. 14, the absorbent main body 50 has a non-skin contact surface of the back sheet 80 of the absorbent main body 50 with an inner layer sheet 61 of the outer packaging material 60 by a bonding method using an adhesive, heat seal, ultrasonic seal or the like. It is joined to the skin contact surface.
As shown in FIG. 14, side cuffs 55, 55 made of a liquid-impermeable or water-repellent and breathable material are provided on both sides along the longitudinal direction of the absorbent main body 50. In the vicinity of the free end of each side cuff 55, an elastic member 56 for forming the side cuff is disposed and fixed in an extended state. The side cuff 55 can stand on the free end side when the diaper is worn, and can prevent excrement from flowing out in the width direction of the absorbent main body 50. As shown in FIG. 14, the side cuff 55 forming sheet has a portion 55 a having a predetermined width on the outer side in the width direction of the absorbent main body 50 wound around the non-skin contact surface side of the absorbent body 40. 40 and the back sheet 80 are fixed. Note that the portion 55 a having a predetermined width may be fixed between the back sheet 30 and the outer packaging material 60.

  The nonwoven fabric 1 of this embodiment is preferably used as the outer layer sheet 62 and the inner layer sheet 61 of the outer packaging material 60 of the pants-type disposable diaper 100 used on the skin contact surface of the wearer. Moreover, it can also be used as the surface sheet 70, the back surface sheet 80, and the side cuff 55 forming sheet. 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 70, a liquid-permeable nonwoven fabric, a perforated film, or a laminate thereof can be used, and as the back sheet 80, a resin film or a laminate of the resin film and the nonwoven fabric can be used. Can do. As the sheet for forming the side cuff 55, a stretchable film, a nonwoven fabric, a woven fabric, or a laminated sheet thereof can be used. As the inner layer sheet 61 and the outer layer sheet 62, a water-repellent nonwoven fabric or the like can be used.

As the absorber 40, those conventionally used for absorbent articles such as disposable diapers can be used without particular limitation. For example, as the absorbent body 40, a fiber aggregate of a fiber material 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 56 for forming side cuffs, the waist elastic member 63, and the leg elastic member 64, 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, in the manufacturing method of the nonwoven fabric 1 of this embodiment described above, the raw material nonwoven fabric 10 is subjected to a partial stretching process, other than using the raw material nonwoven fabric 10 that is heat-treated at a temperature lower than the melting point of the fiber that is configured in a separate step. The heat treatment may be performed at a temperature lower than the melting point of the fibers constituting the raw material nonwoven fabric 10. Specifically, in the manufacturing apparatus for the nonwoven fabric 1, a hot air treatment unit is provided on the upstream side of the partial stretching unit 4, and the raw nonwoven fabric 10 heat-treated by the hot air processing unit is continuously steel-matched in the partial stretching unit 4. It may be conveyed between the pair of rollers 41 and 42 of the embossing roller 43 and subjected to partial stretching. Thus, by performing a heat treatment and a partial stretching process in a series of flows, there is an effect that the heat treatment is performed to increase the thickness and the touch is further improved.

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

<1>
A nonwoven fabric in which a web containing long fibers is fixed by a heat fusion part,
A part of the long fiber is broken, and only one end part is provided with a fiber fixed by the heat-sealing part,
The portion located between the heat-sealed portions adjacent to each other in the orientation direction of the long fibers is a nonwoven fabric having an elongation of 35% or more with respect to a tensile load of 1 cN / 1 mm.

<2>
The portion located between the heat fusion portions adjacent to each other in the orientation direction of the long fibers preferably has an elongation of 40% or more with respect to a tensile load of 1 cN / 1 mm, and further an elongation of 50% or more. The degree of elongation is preferably 60% or more, more preferably 200% or less, and further preferably 150% or less, particularly 120% or less. The nonwoven fabric according to <1>, preferably having a degree of elongation of.
<3>
The nonwoven fabric according to <1> or <2>, wherein the nonwoven fabric preferably has a breaking strength value of 5.00 N / 50 mm or more and 8 N / 50 mm or more and 30 N / 50 mm or less.
<4>
The ratio of the breaking strength of the raw material nonwoven fabric before breaking a part of the nonwoven fabric and the long fibers (breaking strength of the nonwoven fabric / breaking strength of the raw material nonwoven fabric) is 0.5 or more, preferably 0.7 or more, and 1 The nonwoven fabric according to any one of <1> to <3>, which is 0.0 or less.
<5>
The nonwoven fabric preferably has a bulk softness of 4.5 cN or less, more preferably 3 cN or less, still more preferably 2.5 cN or less, and preferably 0.5 cN or more. The compression characteristic value at the time of the minute load is preferably 14.7 (cN / cm ² ) / mm (15 (gf / cm ² ) / mm) or less, preferably 11.8 (cN / cm ² ) / mm ( 12 (gf / cm ² ) / mm) or less, more preferably 10.8 (cN / cm ² ) / mm (11 (gf / cm ² ) / mm) or less, < The nonwoven fabric according to any one of 1> to <4>.
<6>
The amount of the raised fiber including the fiber in which only one end is fixed by the heat fusion part is preferably 10 / cm or more, and more preferably 15 / cm or more. 50 / cm or less, and the height is preferably 0.7 mm or more, more preferably 2.0 mm or more, preferably 5 mm or less, and 3 mm or less. More preferably, the nonwoven fabric according to any one of the above items <1> to <5>.
<7>
The nonwoven fabric before breaking a part of the long fibers preferably has a bulk softness of 10 cN or less, more preferably 6 cN or less, and preferably 1 cN or more, <1> to <1> to The nonwoven fabric according to any one of <6>.
<8>
The nonwoven fabric according to any one of <1> to <7>, wherein the nonwoven fabric before breaking a part of the long fibers is heat-treated at a temperature lower than a melting point of the fibers constituting the nonwoven fabric .

<9>
A method for producing a nonwoven fabric, wherein a part of the nonwoven fabric is partially stretched at a temperature of 50 ° C. or less, and the nonwoven fabric subjected to the partial stretching process is subjected to raising to raise the constituent fibers of the nonwoven fabric,
The raising process is performed using a convex roller having a plurality of convex portions on the peripheral surface,
In the convex roller, in at least one of the rotation axis direction and the circumferential direction, the convex portions are arranged in a random pattern,
The convex roller is a method for producing a nonwoven fabric in which a processing distance obtained by the following formula (1) is 350 mm or more.
<10>
The method for producing a nonwoven fabric according to <9>, wherein the convex portions of the convex roller are arranged in a random pattern in the circumferential direction of the convex roller in the raising process.
<11>
The method for producing a nonwoven fabric according to <9> or <10>, wherein the raised portions of the raised roller are arranged in a random pattern in the direction of the rotation axis of the raised roller in the raising process.
<12>
The processing distance is preferably 350 mm or more, more preferably 800 mm or more, and particularly preferably 1000 mm or more. And the manufacturing method of the nonwoven fabric any one of said <9>-<11> which is preferably 10,000 mm or less, and more preferably 5000 mm or less.
<13>
In the raising process, the rotation direction of the convex roller is rotated in the direction opposite to the conveying direction of the raw material nonwoven fabric, and the convex roller is rotated at a speed of 0.3 to 10 times the conveying speed of the raw material nonwoven fabric. The method for producing a nonwoven fabric according to any one of <9> to <12>.
<14>
The partial stretching process is performed using a 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 into which the convex portion enters the peripheral surface at a position corresponding to the convex portion of the one roller.
The meshing depth between the convex portion of one of the rollers and the convex portion of the other roller is preferably 3.5 mm or more, more preferably 4 mm or more and 10 mm or less, and 4 mm or more and 6 mm or less. Is a nonwoven fabric production method according to any one of the above <9> to <13>.
<15>
In the partial stretching process, the area of the top surfaces of the convex portions of the pair of concavo-convex rollers is preferably 1 mm ² or more and 100 mm ² or less, more preferably 4 mm ² or more and 25 mm ² or less, <14> The manufacturing method of the nonwoven fabric as described.
<16>
In the partial stretching process, the height h ₁ of the convex portions of the first concave and convex rollers constituting the pair of concave and convex rollers is different from the height h ₂ of the convex portions of the second concave and convex rollers. The method for producing a nonwoven fabric according to <14> or <15>, wherein the convex portion is formed higher than the convex portion of the first uneven roller.
<17>
When the first concave convex roll and the second embossing roll engaged to the maximum, when the flat cross section the depth d ₀ of the engagement at the position d _1/2 bisecting said first concave convex roll and A gap of preferably 0.1 mm or more and 10 mm or less, more preferably 0.6 mm or more and 8 mm or less, and even more preferably 0.8 mm or more and 3 mm or less is formed over the entire circumference of each convex portion of the second uneven roll. The manufacturing method of the nonwoven fabric as described in said <16>.
<18>
The partial stretching is performed by pressing between a plurality of convex portions of one roller and a plurality of concave portions of the other roller, and further, a plurality of convex portions of the other roller and one roller. <14> to <17>, wherein the material is sandwiched between a plurality of recesses and stretched in a direction perpendicular to the transport direction and the transport direction at each of a plurality of locations of the raw material nonwoven fabric. Manufacturing method of non-woven fabric.
<19>
The method for producing a nonwoven fabric according to any one of <9> to <18>, wherein a nonwoven fabric having a bulk softness of 10 cN or less is used as the raw material nonwoven fabric.
<20>
The method for producing a nonwoven fabric according to any one of <9> to <19>, wherein the raw material nonwoven fabric is subjected to a heat treatment at a temperature lower than the melting point of the fibers constituting the raw material nonwoven fabric before the partial stretching process.

<21>
An absorbent article using the nonwoven fabric according to any one of <1> to <8> as a constituent member.
<22>
A disposable diaper using the nonwoven fabric according to any one of <1> to <8> as a constituent member.

  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]
A spunbonded nonwoven fabric having a basis weight of 18 g / m ² , a thickness of 0.29 mm, and a bulk density of 16.1 g / cm ^{3 made} of polypropylene resin having a fiber diameter of 16 μm was used as the raw material nonwoven fabric. In addition, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 7.6 cN. Next, this spunbonded nonwoven fabric is partially stretched through a steel matching embossing roller 43 shown in FIGS. 6 and 7, and further raised by a convex roller 51 in which convex portions 511 shown in FIG. 11 are arranged in a random pattern. And the nonwoven fabric of Example 1 was produced. In the steel matching embossing roller 43 used, the depth of engagement between each convex portion 411 of the roller 41 and each convex portion 421 of the roller 42 was 4 mm. Moreover, the height of the convex part 411 is 5 mm, the distance (pitch P ₁ ) between the convex parts 411 adjacent in the circumferential direction is 8.5 mm, and the distance (pitch P) between the convex parts 411 adjacent in the rotation axis direction. ₂ ) was 8.5 mm. Each convex part 421 in the roller 42 of the steel matching embossing roller 43 is the same. Moreover, the processing distance calculated | required by Formula (1) mentioned above was 2435 mm.

[Example 2]
The same raw material nonwoven fabric as in Example 1 is used, and a two-step process is performed under the same conditions as in Example 1 except that the convex roller 51 having a processing distance of 864 mm determined by the above-described formula (1) is used. A non-woven fabric was prepared.

Example 3
The same raw material nonwoven fabric as in Example 1 is used, and a two-step process is performed under the same conditions as in Example 1 except that the convex roller 51 having a processing distance of 393 mm determined by the above-described formula (1) is used. A non-woven fabric was prepared.

Example 4
Using a spunbonded nonwoven fabric having a basis weight of 17 g / m ² , a thickness of 0.26 mm, and a bulk density of 15.3 g / cm ^{3 made} of polypropylene resin having a fiber diameter of 16 μm as the raw material nonwoven fabric, the processing required by the above formula (1) A nonwoven fabric of Example 4 was produced by performing two-stage treatment under the same conditions as in Example 1 except that the convex roller 51 having a distance of 370 mm was used. In addition, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 4.2 cN.

Example 5
As a raw material nonwoven fabric, a spunbond nonwoven fabric having a basis weight of 18 g / m ² , a thickness of 0.27 mm, and a bulk density of 15.0 g / cm ^{3 made} of a polypropylene resin having a fiber diameter of 18 μm is used, and the processing required by the above-described formula (1) A nonwoven fabric of Example 5 was produced by performing two-stage treatment under the same conditions as in Example 1 except that the convex roller 51 having a distance of 707 mm was used. In addition, the bulk softness of the raw material nonwoven fabric measured based on the above-described bulk softness measurement method was 10 cN.

[Comparative Example 1]
The same raw material nonwoven fabric as in Example 1 was used. As the steel matching embossing roller for performing the partial stretching process, a pair of rollers having a meshing depth of 3 mm between each convex portion of one roller and each convex portion of the other roller was used. In the convex roller to which the raising process is performed, the convex portions are arranged in a regular pattern, and the processing distance obtained by the above-described formula (1) is 393 mm. Otherwise, the nonwoven fabric of Comparative Example 1 was produced by performing two-stage treatment under the same conditions as in Example 1.

[Comparative Example 2]
The raw material nonwoven fabric used in Example 1 was used as the nonwoven fabric of Comparative Example 2. The nonwoven fabric of Comparative Example 2 was not particularly subjected to partial stretching or raising.

[Performance evaluation]
About the nonwoven fabric of Examples 1-3 and Comparative Examples 1-2, while measuring a basic weight, thickness, and bulk density by a usual method, according to the method mentioned above, the elongation of the part located between heat-fusion parts, fracture | rupture The strength, bulk softness, compression characteristic value at a minute load, the amount of raised fibers, and the height of raised fibers were measured. Moreover, according to the method mentioned later about the nonwoven fabric of Examples 1-3 and Comparative Examples 1-2, the touch property and the touch feeling were evaluated, respectively. The evaluation environment was a room temperature of 20 ° C. and a humidity of 60% RH. The results are shown in Table 1 below.

[Elongation of the part located between the heat-sealed parts]
Based on the above-described method for measuring the elongation of the portions located between the heat fusion portions, the elongation of the portions located between the heat fusion portions in the nonwoven fabrics of Examples 1-3 and Comparative Examples 1-2. The degree was measured.

[Skin feel]
For the nonwoven fabrics obtained in Examples 1 to 3 and Comparative Examples 1 to 2, sensory evaluation of 5 levels (better touching 5 points) when the original nonwoven fabric was used as a reference (1 point) was evaluated to 5 people The results are shown in Table 1. The average value of all the values was calculated by rounding off to the nearest whole number. In addition, this evaluation is sensory evaluation when touching each nonwoven fabric as shown in FIG.

[Feeling of touch]
For the nonwoven fabrics obtained in Examples 1 to 3 and Comparative Examples 1 to 2, sensory evaluation of 5 levels (better touching 5 points) when the original nonwoven fabric was used as a reference (1 point) was evaluated to 5 people The results are shown in Table 1. The average value of all the values was calculated by rounding off to the nearest whole number. In addition, this evaluation is sensory evaluation when touching each nonwoven fabric lightly as shown in FIG.

  As is clear from the results shown in Table 1, it was found that the nonwoven fabrics of Examples 1 to 3 were excellent in touch and excellent touch feeling compared to the nonwoven fabrics of Comparative Examples 1 and 2. It turned out that the nonwoven fabric of Examples 1-2 is further excellent in touch property compared with the nonwoven fabric of Example 3, and is also excellent in a touch feeling. These results show that the nonwoven fabrics of Examples 1 to 3 have a higher elongation at the portion located between the heat-sealed portions than the nonwoven fabrics of Comparative Examples 1 and 2, and the nonwoven fabrics of Examples 1 and 2 were implemented. This is also supported by the fact that the nonwoven fabric of Example 3 has a higher elongation.

DESCRIPTION OF SYMBOLS 1 Nonwoven fabric 2 Long fiber 20 Fiber in which only one end is fixed by thermal fusion part 3 20a One end part 21 Loop-like fiber 3 Thermal fusion part 200 Manufacturing apparatus 4 Partial stretching part 41, 42 A pair of rollers 411 421 Convex part 412, 422 Concave part 43 Steel matching embossing roller 44, 45 Conveying roller 5 Brushed part 51 Convex roller 511 Convex part 52, 53 Conveying roller 10, 10 'Raw material nonwoven fabric 104 Measurement sample 105 Crease 106a Fiber 107 hole traversing twice 108 Virtual line 100 Pants-type disposable diaper 40 Absorber 50 Absorbent body 55 Side cuff 55a
56 Elastic member 60 for forming side cuffs Outer packaging material 61 Inner layer sheet 62 Outer layer sheet 63 Waist part elastic member 64 Leg part elastic member 70 Top sheet 80 Back sheet A Back side part, B Abdominal side part, C Inseam

Claims (11)

A nonwoven fabric in which a web containing long fibers is fixed by a heat fusion part,
A part of the long fiber is broken, and only one end part is provided with a fiber fixed by the heat-sealing part,
The portion located between the heat-sealed portions adjacent to each other in the orientation direction of the long fibers is a nonwoven fabric having an elongation of 35% or more with respect to a tensile load of 1 cN / 1 mm. The non-woven fabric has a bulk softness of 4.5 cN or less and a compression characteristic value at a minute load of 14.7 (cN / cm ² ) / mm (15 (gf / cm ² ) / mm) or less. Item 10. The nonwoven fabric according to item 1.   The portion located between the heat-sealed portions adjacent to each other in the orientation direction of the long fibers has an elongation of 40% or more and 200% or less with respect to a tensile load of 1 cN / 1 mm. Non-woven fabric.   2. The raised fiber including the fiber in which only one end is fixed by the heat fusion part has an amount of 10 fibers / cm or more and a height of 0.7 mm or more. The nonwoven fabric of any one of -3.   The nonwoven fabric according to any one of claims 1 to 4, wherein the nonwoven fabric before breaking a part of the long fibers has a bulk softness of 10 cN or less.   The nonwoven fabric according to any one of claims 1 to 5, wherein the nonwoven fabric before breaking a part of the long fibers is heat-treated at a temperature lower than the melting point of the fibers constituting the nonwoven fabric. A method for producing a nonwoven fabric, wherein a part of the nonwoven fabric is partially stretched at a temperature of 50 ° C. or less, and the nonwoven fabric subjected to the partial stretching process is subjected to raising to raise the constituent fibers of the nonwoven fabric,
The raising process is performed using a convex roller having a plurality of convex portions on the peripheral surface,
In the convex roller, the convex portion is arranged in a random pattern in at least one of the rotation axis direction and the circumferential direction,
The convex roller is a method for producing a nonwoven fabric in which a processing distance obtained by the following formula (1) is 350 mm or more.
The partial stretching process is performed using a 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 into which the convex portion enters the peripheral surface at a position corresponding to the convex portion of the one roller.
The manufacturing method of the nonwoven fabric of Claim 7 whose meshing depth of the convex part of one said roller and the convex part of the other said roller is 3.5 mm or more and 10 mm or less.   The manufacturing method of the nonwoven fabric of Claim 7 or 8 which uses the nonwoven fabric whose bulk softness is 10 cN or less as a raw material nonwoven fabric.   The method for producing a nonwoven fabric according to any one of claims 7 to 9, wherein the raw material nonwoven fabric is subjected to a heat treatment at a temperature lower than the melting point of the fibers constituting the raw material nonwoven fabric before the partial stretching process.   The absorbent article which used the nonwoven fabric of any one of Claims 1-6 as a structural member.