JP2016013192A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorbent article compatibly achieving durability and plasticity.SOLUTION: The absorbent article includes an absorber having the longitudinal direction and width direction orthogonally crossing with each other, and absorbing humor, where the absorber includes pulp fibers and synthetic fibers. The absorber includes a plurality of slits, the angle of which formed with a width-directional virtual line dividing the longitudinal direction into two, is less than 45°, disposed at intervals apart in the longitudinal direction and the width direction respectively. An average length of the synthetic fibers is longer than a maximum slit interval distance that is the longest distance of distances between the slit and a slit adjacent thereto in the longitudinal direction.

Description

  The present invention relates to an absorbent article. More specifically, the present invention relates to an absorbent article such as a sanitary napkin.

It is composed of a liquid-permeable top sheet, a liquid-impervious back sheet, and a liquid-absorbing panel interposed between the front and back sheets, and the panel comprises a fluff pulp, a superabsorbent polymer, and a heat-fusible composition. A nonwoven fabric layer made of heat-fusible synthetic resin fibers is disposed on at least one of the upper and lower surfaces of the body fluid absorption holding layer made of resin fibers, and the absorption holding layer and the nonwoven fabric layer are integrally covered with a water-permeable sheet. In the bonded disposable wearing article, the heat-fusible synthetic resin fiber and the nonwoven fabric layer contained in the absorption-holding layer are heat-bonded to each other at the contact surface between the absorption-holding layer and the nonwoven fabric layer. Such an article is known (Patent Document 1).
In the article described in Patent Document 1, synthetic fibers longer than pulp fibers are randomly arranged in the absorbent body, and the fibers are joined by entanglement or heat fusion to serve as a skeleton in the absorbent body. Even if it is used for a long time, a certain durability can be secured without destroying the absorber. Also, the longer the fiber length, the greater the durability.

JP 2002-11047 A

However, in the article described in Patent Document 1, the more the long synthetic fibers are distributed, the more the durability is enhanced. On the other hand, the absorber rigidity is increased, and only the conventional pulp fibers are used. Rigidity rises compared with it, and a feeling of wearing is spoiled.
An object of the present invention is to provide an absorbent article having both durability and flexibility.

The present inventors, in an absorbent body in which pulp fibers and synthetic fibers are blended, in the absorbent body, a plurality of slits extending in the width direction are arranged at intervals in the longitudinal direction and the width direction, respectively. It has been found that the above problem can be solved by shortening the slit interval in the longitudinal direction rather than the fiber length of the blended synthetic fiber, and the present invention has been completed.
That is, the present invention is a vertically long absorbent article having a longitudinal direction and a width direction orthogonal to each other and having an absorbent body that absorbs body fluid, the absorbent body including pulp fibers and synthetic fibers, In the body, a plurality of slits having an angle of less than 45 degrees formed by a width imaginary line that bisects the longitudinal direction are arranged at intervals in the longitudinal direction and the width direction, the longitudinal direction of the slit and the slit. Among the distances between adjacent slits, the average length of the synthetic fibers is longer than the maximum inter-slit distance, which is the longest distance.

  In the absorbent article of the present invention, the absorber has both durability and flexibility.

FIG. 1 is a partially broken plan view of one embodiment of the absorbent article of the present invention. 2 is a schematic cross-sectional view taken along the line II ′ of FIG. FIG. 3 is a schematic cross-sectional view of another embodiment of the absorbent article of the present invention. FIG. 4 is a diagram illustrating an example of a staggered arrangement of slits. FIG. 5 is a diagram showing a modification of the staggered arrangement of slits. FIG. 6 is a diagram illustrating another modification of the staggered arrangement of slits. FIG. 7 is a diagram illustrating another example of the slit arrangement. FIG. 8 is a diagram illustrating one example of the slit arrangement. FIG. 9 is a diagram showing an example of an absorbent article manufacturing apparatus according to the present invention.

The present invention will be described below with reference to the drawings, but the present invention is not limited to those shown in the drawings.
FIG. 1 is a partially cutaway plan view of an embodiment of an absorbent article of the present invention, and FIG. 2 is a schematic cross-sectional view taken along the line II ′ of FIG. The absorbent article 1 shown in FIG. 1 is a sanitary napkin. The absorbent article 1 was provided between a liquid-permeable top sheet 2 provided on the skin side, a liquid-impermeable back sheet 3 provided on the clothing side, and the top sheet and the back sheet. It has a longitudinal direction and a width direction perpendicular to each other, and an absorbent body 4 that absorbs body fluid. Although the absorbent article 1 shown in FIG. 1 has a pair of wings 5 and 5, a wing is not essential. The absorber 4 includes pulp fibers 7 and synthetic fibers 8. In the absorber, a plurality of slits 6 with an angle of less than 45 degrees formed by a width direction imaginary line dividing the longitudinal direction into two are arranged at intervals in the longitudinal direction and the width direction. Of the distances between the slits and the slits adjacent to each other in the longitudinal direction of the slits, the average length of the synthetic fibers is longer than the maximum inter-slit distance which is the longest distance.

  FIG. 3 is a schematic cross-sectional view of another embodiment of the absorbent article of the present invention. In the embodiment shown in FIG. 3, in addition to the components of the embodiment shown in FIG. 2, the water-absorbing polymer 9 is included in the absorbent body 4, and the sheet 10 made of heat-fusible fibers is arranged on one side of the absorbent body 4. Has been.

  The absorber 4 has a slit 6. The slit 6 has a finite length, and a plurality of slits 6 are arranged at intervals in the longitudinal direction and the width direction. The angle formed by the slit 6 with the imaginary line in the width direction that bisects the longitudinal direction is 0 degree or more and less than 45 degrees. The arrangement pattern of the slits 6 is not limited. For example, a zigzag arrangement, a parallel arrangement, and modifications thereof can be exemplified, but a zigzag arrangement is preferable. The slit arrangement shown in FIG. 1 is an example of a staggered arrangement.

In the present application, the “maximum distance between slits” refers to a distance having the longest length among distances between a slit and a slit adjacent in the longitudinal direction of the slit.
Here, “a slit adjacent in the longitudinal direction” refers to one slit, draws a straight line parallel to the longitudinal direction from a point X on the slit, and obtains a point Y where the straight line intersects with another slit. Other slits in which the length of the line segment XY is the shortest.
FIG. 4 is an example of a staggered slit. In FIG. 4, the arrow indicates the longitudinal direction. When paying attention to the slit 6a and drawing a straight line parallel to the longitudinal direction from a point on the slit 6a, the straight line intersects any one of the slits 6b, 6c, 6d, 6e, 6f, and 6g. The length of the line segment X _b Y _b connecting the point Y _b where the straight line parallel to the longitudinal direction drawn from the point X _b on the slit 6a intersects the slit 6b and the point X _b on the slit 6a, and the slit 6a The length of a line segment X _c Y _c connecting a point Y _c where a straight line parallel to the longitudinal direction drawn from the point X _c intersects the slit 6c and the point X _c on the slit 6a, and a point X on the slit 6a _The length of a line segment X _d Y _d connecting a point Y _d where a straight line parallel to the longitudinal direction drawn from _d intersects the slit 6d and the point X _d on the slit 6a and the point X _e on the slit 6a are drawn. The lengths of X _e Y _e connecting the point Y _e where the straight line parallel to the longitudinal direction intersects with the slit 6 _e and the point X _e on the slit 6 a are equal, and are in the longitudinal direction drawn from the point _f on the slit 6 a. line parallel straight lines connecting the points X _f on the slit 6a and the point Y _f intersecting the slit 6f A line segment X _g Y connecting a point Y _g where a straight line parallel to the length of the segment X _f Y _f and the point _g on the slit 6a intersecting the longitudinal direction intersects the slit 6g and the point X _g on the slit 6a. the length of _g, the line segment X _b Y _b, the line segment X _c Y _c, the line segment X _d Y _d, longer than the length of the line segment X _e Y _e. That is, the shortest line segment XY is the line segment X _b Y _b , line segment X _c Y _c , line segment X _d Y _d , line segment X _e Y _e , and the length of the line segment XY is the shortest. The other slits are slits 6b, 6c, 6d, and 6e. Therefore, in this slit arrangement, there are four slits 6b, 6c, 6d and 6e adjacent in the longitudinal direction, and the slits 6f and 6g are not slits adjacent in the longitudinal direction.

FIG. 5 shows a modified example of the staggered arrangement. In FIG. 5, the arrow indicates the longitudinal direction. In the slit arrangement of FIG. 4, all the slits extend in parallel, but in the slit arrangement of FIG. 5, there are two types of directions in which the slits extend, and not all the slits extend in parallel. When attention is paid to the slit 6h and a straight line parallel to the longitudinal direction is drawn from a point on the slit 6h, the straight line intersects any one of the slits 6i, 6j, 6k, 6l, 6m, and 6n. Since the slit 6h and the slit 6i are not parallel, the length of the line segment connecting the point where the straight line parallel to the longitudinal direction drawn from the point on the slit 6h intersects the slit 6i and the point on the slit 6h is not constant. The length of the line segment X _i Y _i connecting the point Y _i where the straight line parallel to the longitudinal direction drawn from the right end point X _i of the slit 6 h intersects the slit 6 _i and the point X _i on the slit 6 h is the longest. short. Similarly, the shortest line segment connecting the points on the slit 6h connecting a point parallel to the longitudinal direction drawn from the point on the slit 6h and the point on the slit 6h is the right end of the slit 6j. a line X _j Y _j through the points Y _j of the longitudinal direction in a parallel straight line drawn from a point on the slit 6h is of a line connecting the point on the slit 6h a point which intersects the slits 6k length The shortest line segment is a line segment X _k Y _k passing through the left end point X _k of the slit 6h. The straight line parallel to the longitudinal direction drawn from the point on the slit 6h intersects the slit 61 and Of the lengths of the line segments connecting the points on the slit 6h, the shortest line segment is a line segment X _l Y _l passing through the left end point Y _l of the slit 6l. The lengths of the line segment X _i Y _i , line segment X _j Y _j , line segment X _k Y _k, and line segment X _l Y _l are equal. The length of the line segment X _m Y _m connecting the point Y _m where the straight line parallel to the longitudinal direction drawn from the point X _m on the slit 6h intersects the slit 6m and the point X _m on the slit 6h and on the slit 6h The length of the line segment X _n Y _n connecting the point Y _n where the straight line parallel to the longitudinal direction drawn from the point X _n intersects the slit 6 _n and the point X _n on the slit 6 h is the line segment X _i Y _i, the line segment X _j Y _j, the line segment X _k Y _k, than the length of the line segment X _l Y _l long. That is, the shortest line segment XY is the line segment X _i Y _i , line segment X _j Y _j , line segment X _k Y _k , line segment X _l Y _l , and the length of the line segment XY is the shortest. The other slits are slits 6i, 6j, 6k, and 6l. Therefore, in this slit arrangement, there are four slits 6i, 6j, 6k, 6l adjacent in the longitudinal direction, and the slits 6m, 6n are not slits adjacent in the longitudinal direction.

Here, the “distance between the slit and the slit adjacent in the longitudinal direction of the slit” is a point Y where a straight line parallel to the longitudinal direction drawn from the point X on the slit intersects with the slit adjacent in the longitudinal direction. And the length of a line segment XY connecting the point X on the slit.
4, the distance between the slit 6b adjacent to the longitudinal direction of the slit 6a and the slit 6a is the length of the line segment X _b Y _b, between the slits 6c adjacent to the slit 6a and therewith the longitudinal direction the distance is the length of the line segment X _c Y _c, distance between the slit 6d adjacent to the longitudinal direction of the slit 6a and the slit 6a is the length of the line segment X _d Y _d, a slit 6a and the slit 6a the distance between the slit 6e adjacent to the longitudinal direction of the is the length of the line segment X _e Y _e.
When the slit and the slit adjacent in the longitudinal direction of the slit are not parallel as in the slit arrangement of FIG. 5, the “distance between the slit and the slit adjacent in the longitudinal direction of the slit” The maximum length among the lengths of line segments XY connecting a point Y where a straight line parallel to the longitudinal direction drawn from the point X intersects a slit adjacent in the longitudinal direction and the point X on the slit is assumed. Of the lengths of line segments connecting a point where a straight line parallel to the longitudinal direction drawn from a point on the slit 6h intersects the slit 6i and a point on the slit 6h, the longest line segment is a point Y at the left end of the slit 6i. _Since it is the line segment X _i ′ Y _i ′ passing through _i ′, the distance between the slit 6h and the slit 6i adjacent in the longitudinal direction of the slit 6h is the length of the line segment X _i ′ Y _i ′. Similarly, the distance between the slit 6h and the slit 6j adjacent to the longitudinal direction of the slit 6h is the length of the line segment X _j ′ Y _j ′, and the slit 6k and the slit 6k adjacent to the longitudinal direction of the slit 6h Is the length of the line segment X _k ′ Y _k ′, and the distance between the slit 6h and the slit 6l adjacent in the longitudinal direction of the slit 6h is the length of the line segment X _l ′ Y _l ′. is there.

Next, “the distance having the longest length among the distances between the slit and the slit adjacent in the longitudinal direction of the slit” will be described.
4 and 5, when the distance between the slit and the slit adjacent in the longitudinal direction of the slit is the same regardless of which slit is focused as in the slit arrangement of FIGS. Among the distances between adjacent slits in the longitudinal direction, the length is the longest distance ”. In the slit arrangement of FIG. 4, the lengths of the line segment X _b Y _b , the line segment X _c Y _c , the line segment X _d Y _d , and the line segment X _e Y _e are “the slit and the slit adjacent to the longitudinal direction of the slit”. Is the longest distance among the distances between the two, that is, the “maximum distance between slits”. In the slit arrangement of FIG. 5, the lengths of the line segment X _i Y _i , line segment X _j Y _j , line segment X _k Y _k , and line segment X _l Y _l are “the slit and the slit adjacent to the longitudinal direction of the slit”. Is the longest distance among the distances between the two, that is, the “maximum distance between slits”.
FIG. 6 shows another modification of the staggered arrangement, and the distance between the slit and the slit adjacent in the longitudinal direction of the slit increases from the bottom to the top. In FIG. 6, the arrow indicates the longitudinal direction. The distance between the slit adjacent to the longitudinal direction of the slit 6q and the slit 6q may line X _o Y _o, the line segment X _p Y _p, the line segment X _r Y _r, the length of the line segment X _s Y _s is there. The distance between the slit adjacent to the longitudinal direction of the slit 6t and slits 6t is a line segment X _r 'Y _r', the line segment X _s 'Y _s', the line segment X _u Y _u, the line segment X _v Y _v And longer than the distance between the slit 6q and the slit adjacent to the longitudinal direction of the slit 6q. The distance between the slit 6w and the slit adjacent to the longitudinal direction of the slit 6w is as follows: line segment X _u ′ Y _u ′, line segment X _v ′ Y _v ′, line segment X _x Y _x , line segment X _y Y _y It is longer than the distance between the slit 6t and the slit adjacent to the longitudinal direction of the slit 6t. Therefore, in this arrangement, the distance between the slit and the slit adjacent in the longitudinal direction of the slit is the line segment X _o Y _o , line segment X _p Y _p , line segment X _r Y _r , line segment X _s Y _s length, line segment X _u ′ Y _u ′, line segment X _v ′ Y _v ′, line segment X _x Y _x , line segment X _y Y _y length, and line segment X _u ′ Y _u ′ , Line segment X _v ′ Y _v ′, line segment X _x Y _x , and line segment X _y Y _y , there are three types of lengths, and among these three lengths, line segment X _u ′ The lengths of Y _u ′, line segment X _v ′ Y _v ′, line segment X _x Y _x , and line segment X _y Y _y are the longest. Therefore, in this arrangement, the lengths of the line segment X _u ′ Y _u ′, line segment X _v ′ Y _v ′, line segment X _x Y _x , and line segment X _y Y _y are “ Among the distances between adjacent slits in the longitudinal direction, the distance is the longest length, that is, the “maximum distance between slits”. In the case of the arrangement of FIG. 6, there are three types of distances between the slits and the slits adjacent in the longitudinal direction of the slits, but there are four or more types of distances between the slits and the slits adjacent to the slits in the longitudinal direction. In this case, the longest of the four or more types of distances is the maximum slit distance.

  The present invention is characterized in that the average length of the synthetic fiber is longer than the maximum distance between the slits. Here, the average length of synthetic fibers refers to the average length of synthetic fibers to be blended when pulp fibers and synthetic fibers are blended to produce an absorbent body, and the length before being cut by a slit. Say. By arranging a synthetic fiber having a long fiber length, a repulsive force is exerted on the absorber. At that time, if the slit extends in the width direction, the repulsion action by the blended fiber is utilized 100% in the product width direction, but the synthetic fiber is partially cut by the slit in the longitudinal direction. Therefore, the resilience is inferior, but a certain degree of flexibility is imparted. In the width direction, durability is important because it receives compression from the crotch, and it is desirable that the longitudinal direction be flexible in order to easily follow the curve of the body.

In addition, the average length of the synthetic fiber is measured on a glass plate with a scale of “A7.1.1 A method (standard method)” in “A7.1 Measurement of fiber length” in Annex A of JIS L 1015: 2010. It measures according to the method of measuring the length of individual fibers.
When measuring the average length of the synthetic fiber from the sample of the absorber, a plurality of synthetic fibers not cut by the slit are selected from the sample of the absorber, and their lengths are measured and averaged.

  The slit has a finite length. The length of the slit is preferably 3 to 30 mm, more preferably 5 to 15 mm. If it is short, the effect as a slit which gives flexibility is not born. If the length is long, when the absorbent body is compressed from the outside in the width direction, the absorbent body is cracked so as to open its mouth, and there is a risk that problems such as durability may occur.

  The angle between the slit and the imaginary line in the width direction that bisects the longitudinal direction is 0 degree or more and less than 45 degree, preferably 40 degree or less. When the angle with respect to the width direction is too large, the fibers oriented in the width direction are easily cut, which affects the durability in the width direction.

  It is preferable that the end point of the slit adjacent to the width direction does not exist on the extended line of the slit. In other words, it is preferable that the extending direction of the slit does not coincide with the width direction. In the embodiment of FIG. 1, the extending direction of the slit coincides with the width direction, and the end points of the slit adjacent in the width direction exist on the extension line of the slit. FIG. 7 shows another example of the slit arrangement. In FIG. 7, the arrow indicates the longitudinal direction. In this example, there is no end point of the slit adjacent in the width direction on the extension line of the slit. In other words, the slit is slightly inclined with respect to the width direction. When a slit is formed using a cutter roll, the blade for forming the slit is tilted from the width direction so that the blade contacts at a point during production, so the slit can be formed with a small pressure, and the load applied to the blade Is reduced, and there is an effect of improving the holding of the blade. In order to obtain this effect, the angle with respect to the width direction is preferably 1 to 40 degrees, more preferably 2 to 30 degrees, and further preferably 3 to 20 degrees.

  As shown in FIG. 1, it is preferable that the slit does not reach the side edge in the width direction of the absorber. By preventing the slit from reaching the side edge in the width direction of the absorbent body, it is possible to prevent the absorbent body from being broken based on the slit due to compression of the crotch.

  It is preferable that the slit does not penetrate in the thickness direction of the absorber. When the slit penetrates the absorber, the strength of the absorber is reduced, and the absorber may be easily broken. The depth of the slit is preferably 10 to 80% of the thickness of the absorber, more preferably 20 to 70% of the thickness of the absorber, and further preferably 30 to 60% of the thickness of the absorber. If the depth of the slit is too small, the effect of lowering the rigidity is not sufficiently exhibited. If the depth of the slit is too large, the durability will be insufficient, the absorber will be destroyed during use, and it will be difficult for the body fluid to diffuse in the longitudinal direction, increasing the risk that the body fluid will spread laterally.

  It is preferable that the absorber under the slit is compressed. Durability is imparted by compressing the fragile absorber that is easily broken by the slit. As shown in FIG. 3, a recess 11 is formed on the surface of the absorbent body 4 on the back sheet 3 side at a position corresponding to the position where the slit 6 is formed. That is, in this example, the absorber under the slit is compressed.

The absorbent article of the present invention is an absorbent article that can be used to absorb bodily fluids such as menstrual blood and urine, and more specifically, sanitary napkins, urine picking pads, and the like.
The absorbent article of the present invention includes a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent that absorbs body fluid.

  The top sheet has a function of allowing liquid excretion from the body, such as menstrual blood and urine, to pass through the absorber provided in the lower layer, and holds the absorber by sandwiching the absorber with the back sheet. Is for. The top sheet is liquid permeable in whole or in part, and the liquid permeable region includes a resin film having a large number of liquid permeable holes, a net-like sheet having a large number of meshes, a liquid permeable nonwoven fabric, or a woven material. Formed with cloth or the like.

  The backsheet has a function of preventing liquids such as menstrual blood and urine absorbed by the absorber from leaking out, and a material that can prevent such liquid from leaking out is used. The Moreover, by using a material that does not allow liquid to pass through but is breathable, it is possible to reduce stuffiness during wearing and to reduce discomfort during wearing. Examples of such a material include a liquid-impermeable film mainly composed of polyethylene (PE), polypropylene (PP), etc., a breathable film, and a composite in which a liquid-impermeable film is laminated on one side of a nonwoven fabric such as spunbond. A sheet etc. are mentioned.

The absorber includes pulp fibers and synthetic fibers.
The fibers are randomly arranged, and the direction of the fibers extends in both the longitudinal direction and the width direction.
Examples of the pulp fiber include pulp, for example, wood pulp and non-wood pulp obtained from softwood or hardwood. Particularly preferred is a pulverized pulp having a fiber length of about 3 mm.

  The synthetic fiber is not particularly limited, but a synthetic fiber made of an olefin resin is preferable. More preferred are composite fibers such as polyethylene (PE) / polypropylene (PP) and PE / polyethylene terephthalate (PET). By including PE, when heat-sealing with the surface material etc. which consist of an olefin type similarly, it heat-welds and durability is provided.

The absorber preferably further includes a water-absorbing polymer.
The water-absorbing polymer is also called SAP (superabsorbent polymer) and has a three-dimensional network structure in which a water-soluble polymer is appropriately cross-linked, and absorbs water several hundred to thousand times. It is water-insoluble, and once absorbed water does not release even when a certain pressure is applied, starch-based, acrylic acid-based, and amino acid-based water-absorbing polymers are commercially available.

The content of the synthetic fiber in the absorbent body is preferably 7.5 to 100 parts by mass, more preferably 9 to 50 parts by mass, and further preferably 10 to 30 parts by mass with respect to 100 parts by mass of the pulp fiber. It is. If the content of the synthetic fiber is too small, there is a possibility that sufficient durability cannot be imparted to the absorber. When there is too much content of a synthetic fiber, there exists a tendency for the liquid absorptivity of an absorber to become inadequate.
The content of the water-absorbing polymer in the absorber is preferably 5 to 80 parts by mass, more preferably 10 to 60 parts by mass, and further preferably 20 to 40 parts by mass with respect to 100 parts by mass of the pulp fiber. It is. If the content of the water-absorbing polymer is too small, the absorbent property of the absorber tends to be insufficient. When the content of the water-absorbing polymer is too large, the crimped portion tends to become hard.

  The average length of the synthetic fiber is not limited as long as it is longer than the maximum distance between the slits, but is preferably 5 to 50 mm, more preferably 15 to 40 mm, and still more preferably 20 to 35 mm. . The longer the average length of the synthetic fibers, the more easily the rigidity of the fibers is exerted on the entire absorbent body, and the entanglement of the fibers is more likely to occur, thereby improving the durability. On the other hand, if the average length of the synthetic fiber is too long, there is a problem that the fiber opening property of the synthetic fiber is remarkably lowered during the production and blending with the pulp fiber becomes difficult.

The average length of the pulp fibers is shorter than the average length of the synthetic fibers. Although the average length of a pulp fiber is not specifically limited, Preferably it is 0.5-7 mm, More preferably, it is 1-6 mm, More preferably, it is 2-5 mm. If the average length of the pulp fiber is too short, the durability of the absorber cannot be obtained, and there is a risk of yield deterioration such as falling out of the mesh during production.
The average length of pulp fibers means the weight-weighted average length, measured by KajaaniFiberLab fiber properties (off-line) manufactured by metso automation. L (w) value.

  Although the fiber diameter of a synthetic fiber is not limited, Preferably it is 1.5-20 dtex, More preferably, it is 1.8-15 dtex, More preferably, it is 2.0-10 dtex. If the fiber diameter is too thin, it is insufficient for imparting rigidity in terms of durability, and if the fiber diameter is too thick, there is a problem that the absorber becomes too hard.

Although the thickness of an absorber changes with uses, Preferably it is 0.1-15 mm, More preferably, it is 1-10 mm, More preferably, it is 2-5 mm.
In addition, the thickness (mm) of the absorber is a standard state (temperature) using a thickness gauge FS-60DS (measurement surface: circle with a diameter of 44 mm, measurement pressure: 3 g / cm ² ) manufactured by Daiei Scientific Instruments Co., Ltd. 23 ± 2 ° C, relative humidity 50 ± 5%), pressurize 5 different parts of the sample at 3 g / cm ² , measure the thickness after 10 seconds of pressurization, and average the measured values at the 5 places Can be measured by making the thickness of the absorber.

The basis weight of the absorber is preferably 40 to 900 g / m ² , more preferably 50 to 800 g / m ² , and still more preferably 100 to 500 g / m ² . This is from the viewpoint of the strength and absorbability of the absorber.
The basis weight is measured according to “6.2 Mass per unit area (ISO method)” of JIS L 1913: 2010.

Apparent density of the absorbent body is preferably 0.06~0.14g / cm ^3, more preferably 0.07~0.12g / cm ^3, more preferably a 0.08~0.1g / cm ^3. When an absorber has the ratio of the above-mentioned pulp fiber and synthetic fiber, and the said apparent density, there exists a tendency for an absorber to be excellent in liquid absorptivity.
The apparent density of the absorber can be calculated from the basis weight and thickness of the absorber.

In the absorbent article of the present invention, preferably, a sheet made of heat-fusible fibers is disposed on at least one side of the absorbent body. When the sheet | seat which consists of a heat-fusible fiber is arrange | positioned, it is preferable that a slit is formed by cutting together the sheet | seat which consists of a heat-fusible fiber, and an absorber. The longitudinal flexibility can be ensured by cutting the sheet made of the heat-fusible fiber and the absorbent body together.
FIG. 3 is a schematic cross-sectional view of an absorbent article including a sheet made of heat-fusible fibers. The sheet 10 made of heat-fusible fibers is disposed on the surface of the absorber on the top sheet side, and is preferably bonded with an adhesive (not shown). In the embodiment of FIG. 3, the sheet made of heat-fusible fibers is disposed on the top sheet side surface of the absorbent body, but may be disposed on the back sheet side surface of the absorbent body. It may be arranged on both sides. The width of the sheet 10 made of heat-fusible fibers may be the same as the width of the absorber, may be smaller than the width of the absorber, or may be larger than the width of the absorber. It is preferable that it is slightly smaller. The length in the longitudinal direction of the sheet 10 made of heat-fusible fibers is preferably the same as the length in the longitudinal direction of the absorbent body.
The sheet made of heat-fusible fiber is not particularly limited as long as it is a sheet made of heat-fusible fiber, but examples thereof include non-woven fabrics and woven fabrics made of heat-fusible fibers. , Spunlace nonwoven fabric, and air-through nonwoven fabric. The heat-fusible fiber is not particularly limited, and examples thereof include polyethylene fiber and core-sheath composite fiber having a core PP and a sheath PE. When the sheet made of heat-fusible fiber is disposed on the top sheet side surface of the absorber, it is necessary to be liquid permeable, but when it is disposed on the back sheet side surface of the absorber, It may be liquid impermeable.

The slit does not necessarily need to be disposed over the entire surface of the absorber, and may be disposed only in a part of the absorber.
FIG. 8 shows an example of the slit arrangement. In FIG. 8, the arrow indicates the longitudinal direction. The absorber 4 has a front region F, a longitudinal center region _CM, and a rear region B with respect to the longitudinal direction, and has a left region L, a widthwise central region _CC, and a right region R with respect to the width direction. In the embodiment shown in FIG. 8, the slits 6 are disposed only in the front region F and the rear region B, the left region L, and the right region R of the absorber. According to this slit arrangement, since there is no slit in the absorbent core, the durability when wet is maximized, and the surrounding area is always flexible to the movement of the body, realizing a comfortable wearing feeling it can.
In another embodiment, the slits may be disposed only in the front region F and the rear region B of the absorber, or may be disposed only in the left region L and the right region R. Conversely, without providing a slit in the peripheral region, may be arranged slits only in the central region (region for example, the longitudinal central region C a _M and a widthwise center region C _C).

Next, the manufacturing method of the absorbent article of this invention is demonstrated.
FIG. 9 is a diagram showing an example of an absorbent article manufacturing apparatus according to the present invention.
In addition, in FIG. 9, pulp fiber and synthetic fiber are not expressed separately.
A plurality of recesses 102 extending from the peripheral surface 101a toward the center of the suction drum are formed at a predetermined pitch on the peripheral surface 101a of the rotating suction drum 101 as a mold for filling the absorbent material. When the suction drum 101 rotates and the recess 102 enters the material supply unit 103, the absorber material supplied from the material supply unit 103 is deposited in the recess 102 by the suction of the suction unit 104.
The material supply unit 103 with the hood 103a is formed so as to cover the suction drum 101, and the material supply unit 103 supplies a mixture 105 of pulp fibers and synthetic fibers to the recess 102 by air conveyance. The material supply unit 103 includes a water-absorbing polymer supply unit 107 that supplies the water-absorbing polymer 106, and supplies the water-absorbing polymer 106 to the recess 102. The mixture 105 of pulp fibers and synthetic fibers and the water-absorbing polymer 106 (hereinafter also referred to as “absorber raw material”) are deposited in the concave portion 102 in a mixed state, and the absorbent body 108 is formed in the concave portion 102. When producing an absorbent body that does not contain a water-absorbing polymer, supply of the water-absorbing polymer from the water-absorbing polymer supply unit is stopped, or an apparatus that does not have a water-absorbing polymer supply unit is used. That's fine.

Next, the absorbent body 108 formed in the recess 102 moves onto the carrier sheet 110 having the adhesive coated thereon from the coating machine 109.
The carrier sheet 110 later forms a sheet made of heat-fusible fibers between the absorber and the top sheet, but in an embodiment in which the absorbent article does not have a sheet made of heat-fusible fibers, the top sheet A back sheet, an optional auxiliary sheet, or the like can be used as a carrier sheet.

Next, the absorbent body 108 is passed between the pair of cutter rolls 111 and 112 to form a slit. The pair of cutter rolls includes, for example, a roll 112 with a blade and a smooth roll 111.
The shape and arrangement pattern of the blades are the same as the shape and arrangement pattern of the slits.

In this step, the slit 6 is formed, but when forming the slit 6 that does not penetrate in the thickness direction of the absorber, the bottom of the slit 6 and the smooth roll 111 are caused by the pressing force of the blade of the cutter roll 112. The absorbent body under the slit, that is, the absorber under the slit is compressed to form a densified portion, and the absorber protrudes downward with the contact point of the blade (that is, the bottom of the slit 6) as the center. It transforms to become. When the pressing force of the blade is removed, the deformed absorber is restored to the original shape by the elastic force of the fibers constituting the absorber, but the densified portion under the slit 6 is compressed. Since the state where the densified portion is adjacent to the bottom of the slit 6 is maintained without being restored, the concave portion 11 centering on the densified portion is opposite to the surface having the slit 6 of the absorber. Formed on the surface.
According to this method, the slit 6 and the recess 11 can be simultaneously formed in one step, so that the absorbent article can be more efficiently softened, and the slit 6 and the recess 11 Since it is formed so as to have substantially the same shape in a plan view at a corresponding position in the thickness direction of the absorber, a portion between the bottom portion of the slit 6 and the concave portion 11 (that is, the densified portion) ) Can be realized with high accuracy, and a comfortable wearing feeling can be provided to the wearer.

  Next, the top sheet 115 is bonded by a pair of rolls 113 and 114, then the back sheet 118 is bonded by a pair of rolls 116 and 117, and finally cut into the shape of the absorbent article by the cutting rolls 119 and 120. Thus, an absorbent article is obtained.

  The absorbent article of the present invention can be suitably used for sanitary napkins, urine collection pads, and the like.

DESCRIPTION OF SYMBOLS 1 Absorbent article 2 Top sheet 3 Back sheet 4 Absorber 5 Wing 6 Slit 7 Pulp fiber 8 Synthetic fiber 9 Water-absorbing polymer 10 Sheet made of heat-fusible fiber 11 Concave part 101 Suction drum 102 Concave part 103 Material supply part 104 Suction Part 105 Mixture of pulp fiber and synthetic fiber 106 Water-absorbing polymer 107 Water-absorbing polymer supply part 108 Absorber 109 Coating machine 110 Carrier sheet 111,112 Cutter roll 113,114 Roll 115 Top sheet 116,117 Roll 118 Back Sheet 119, 120 Cutting roll

Claims (7)

  An absorbent article having a longitudinal direction and a width direction perpendicular to each other and having an absorbent that absorbs body fluid, wherein the absorbent includes pulp fibers and synthetic fibers, and the absorbent includes the longitudinal direction. A plurality of slits having an angle of less than 45 degrees with the imaginary line in the width direction divided into two are arranged at intervals in the longitudinal direction and the width direction, respectively, and between the slit and the slit adjacent to the longitudinal direction of the slit. The absorbent article characterized in that the average length of the synthetic fibers is longer than the maximum inter-slit distance, which is the longest distance among the distances.   The absorbent article according to claim 1, wherein the slit does not reach a side edge in the width direction of the absorber.   The absorbent article according to claim 1 or 2, wherein an end point of a slit adjacent in the width direction does not exist on an extension line of the slit.   A sheet made of heat-fusible fiber is disposed on one side of the absorber, and the slit is formed by cutting together the sheet made of heat-fusible fiber and the absorber. The absorptive article according to any one of claims 1 to 3 characterized by things.   The absorbent article according to any one of claims 1 to 4, wherein the slit does not penetrate in the thickness direction of the absorber.   The absorbent article according to any one of claims 1 to 5, wherein an absorbent body under the slit is compressed.   The absorber has a front region, a longitudinal center region and a rear region with respect to the longitudinal direction, and has a left region, a width direction central region and a right region with respect to the width direction, and the slit is the front region of the absorber and The absorbent article according to any one of claims 1 to 6, wherein the absorbent article is disposed only in the rear region and / or the left region and the right region.

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