JP2010119689A - Absorbent article - Google Patents

Abstract

The present invention provides an absorbent article that does not give the wearer a sense of incongruity and can be easily peeled off from clothing such as shorts.
An absorbent article of the present invention includes a top sheet 2 that forms a skin facing surface, a back sheet 3 that forms a clothing facing surface, and an absorbent body 3 disposed between the two sheets. The sheet 3 is provided with a fastening portion 7 for fixing to a garment, and the back sheet 3 has a stretchable portion 31 and a non-stretchable portion 32, and is provided on the left and right sides of the front end side of the absorbent article. The stretchable part 31 is located in the corners 1a, 1a, the non-stretchable part 32 is located in the central region in the width direction of the absorbent article, and the fastening is provided on the non-stretchable part 32 in the central region. Part 7 is provided.
[Selection] Figure 1

Description

  The present invention relates to an absorbent article such as a sanitary napkin, a panty liner (cage sheet), and an incontinence pad.

DESCRIPTION OF RELATED ART Conventionally, absorbent articles, such as a sanitary napkin, having a top sheet that forms a skin facing surface, a back sheet that forms a clothing facing surface, and an absorbent body between these two sheets are widely known.
In addition, it is also known to use a stretchable sheet as a back sheet that constitutes a clothing-facing surface of an absorbent article. For example, Patent Document 1 discloses a back sheet that is formed by bonding an elastic body to a moisture-permeable sheet. Patent Document 2 describes that a region having no stretchability but having moisture permeability and a region having no moisture permeability but having stretchability are alternately arranged in multiple rows by coextrusion molding. In addition, it is described that a porous sheet having a concavo-convex pattern on its surface is used as a back sheet.

Japanese Patent No. 3636223 Japanese Patent No. 3628376

  However, in a conventional absorbent article, particularly an absorbent article provided with an absorbent body between the skin-facing surface and the garment-facing surface and provided with a fastening portion for fixing to the garment on the garment-facing surface, At the time of manufacturing, it is difficult to manufacture a homogeneous absorbent article because the dimensions of the elastic sheet are not stable, or the elastic sheet provided with a fastening part is stretched so that the fastening part can be smoothly removed from the shorts. In some cases, peeling was not possible. Moreover, a non-stretchable part may arise in the junction part of the surface sheet which exists in the peripheral part of an absorbent article, and a back surface sheet, and may give a wearer a discomfort.

  Accordingly, an object of the present invention is to provide an absorbent article that does not give the wearer a sense of incongruity and is easy to peel from clothing such as shorts.

  The present invention comprises a top sheet that forms a skin facing surface, a back sheet that forms a clothing facing surface, and an absorber disposed between both sheets, and is fastened to the back sheet for fixing to the clothing. Part is provided, the back sheet has a stretchable part and a non-stretchable part, the stretchable part is located at the left and right corners of the front end side of the absorbent article, By providing an absorbent article in which the non-stretchable portion is located in a central region in the width direction of the absorbent article, and the fastening portion is provided on the non-stretchable portion of the central region. Is achieved.

  The absorbent article of the present invention does not give the wearer a sense of incongruity and is easy to peel off from clothing such as shorts.

Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings.
A sanitary napkin 1 (hereinafter also simply referred to as a napkin 1) according to an embodiment of the present invention includes a surface sheet 2 that forms a skin facing surface P and a back sheet that forms a clothing facing surface Q, as shown in FIG. 3 and an absorbent body 4 disposed between the two sheets, and the back sheet 3 is provided with a fastening portion 7 for fixing the napkin 1 to clothing. The clothing facing surface Q is a surface of the napkin (absorbent article) that faces the inner surface of clothing such as shorts. The inner surface of the garment is the surface of the garment that is directed toward the wearer's skin.
The napkin 1 has a main body portion 5 placed on the inner surface side of the shorts (the surface side facing the wearer's skin when worn), and wing portions 6 and 6 extending left and right from the main body portion 5. Yes. A pair of wing parts 6 and 6 are formed in the longitudinal direction of the main-body part 5 at the both sides of the excretion part opposing part C which is a site | part arrange | positioned facing a wearer's excretion part at the time of wear.

  The surface sheet 2 in the napkin 1 includes a liquid-permeable central sheet 21 and a pair of liquid-impermeable or water-repellent side sheets 22 and 22. The center sheet 21 has a width that is slightly larger than the width of the absorbent body 4 and extends over the entire length of the napkin 1. Each of the side sheets 22 and 22 has an outer edge portion 22a that defines the outline of the napkin 1 and a linear inner edge portion 22b, and a joint portion 23 that extends linearly along the longitudinal direction of the napkin 1 (see FIG. 2). In FIG.

As shown in FIG. 1B, the back sheet 3 in the napkin 1 includes an elastic part 31 and non-elastic parts 32, 33, 34. The hatched portions in FIG. 1 (b) are non-stretchable portions 32, 33, 34 of the back sheet 3.
As shown in FIG. 1 (b), the expansion / contraction part 31 in the present embodiment is formed in a strip shape on each of both side parts of the main body part 5 so as to cover the substantially entire length of the napkin 1.
A part of the expansion / contraction part 31 is located at the left and right corners 1a, 1a on the front end side of the napkin 1, and the other expansion / contraction part 31 is also provided at the left and right corners 1b, 1b on the rear end side of the napkin 1. Some are located. Furthermore, the expansion / contraction part 31 is located also in the both side parts 1c and 1c of the main-body part 5 in the excretion part opposing part C. FIG. The front end of the napkin 1 is an end portion disposed on the wearer's abdomen side when worn, and the rear end of the napkin 1 is an end portion disposed closer to the wearer's back when worn.

  On the other hand, as shown in FIG. 1B, the non-stretchable portion 32 of the back sheet 3 is located in the center region in the width direction of the napkin 1. Further, the non-stretchable portion 33 of the back sheet 3 is located at the wing portions 6, 6, and the non-stretchable portion 34 of the backsheet 3 is located at the rear flap portions 8, 8. The rear flap portions 8 and 8 are portions located on the outer sides of both side edges of the absorbent body 4 in the portion located behind the excretory portion facing portion C, and on the inner surface of clothing such as shorts when the napkin 1 is attached. Placed in.

  As a back sheet having a stretchable part and a non-stretchable part, a sheet in which an elastomer resin and a non-stretchable resin are coextruded to integrally form a stretchable part and a non-stretchable part, or a stretchable sheet and a non-stretchable sheet Alternatively, fibers or fiber aggregates are partially attached to form a non-stretchable part, and other than the non-stretchable part is used as a stretchable part. The elastomer resin and elastomer resin are mixed with various particles and fibers to reduce stretchability. A sheet in which stretchable parts and non-stretchable parts are integrally formed by co-extrusion with the modified elastomer resin, and a sheet that can be stretched by subjecting a part of the non-stretchable resin to three-dimensional processing such as pleating. You can also.

As the elastomer resin, a thermoplastic elastomer or the like can be used without particular limitation. For example, low density polyethylene using a metallocene catalyst having a density of 0.90 g / cm ³ or less, SBS (styrene-butadiene-styrene), SIS (styrene-isoprene-styrene), SEBS (styrene-ethylene-butadiene-styrene), Styrene elastomers such as SEPS (styrene-ethylene-propylene-styrene), olefin elastomers (propylene elastomers copolymerized with ethylene α-olefin elastomers, ethylene, butene, octene, etc.), polyester elastomers, polyurethane elastomers Or a mixture of two or more thereof. Among these, from the viewpoint of reducing the uncomfortable feeling of mounting, a resin having a low modulus and a small permanent strain is desirable, and a styrene elastomer or a polyolefin elastomer is preferably used.
Examples of the non-stretchable resin include low density polyethylene, low density linear polyethylene polypropylene, polylactic acid, and polybutylene succinate. The non-stretchable resin may contain various additives, plasticizers, and the like.

  Examples of the stretchable sheet in the case where the stretchable portion and the non-stretchable portion are formed by partially attaching the nonstretchable sheet to the stretchable sheet include the above-described sheet made of the thermoplastic elastomer resin. Examples thereof include a sheet made of the above non-stretchable resin, a sheet made of paper, various nonwoven fabrics, and a modified elastomer resin in which various particles and fibers are mixed with an elastomer resin to reduce stretchability.

The stretchable portion 31 of the back sheet 3 preferably has stretchability at least in the longitudinal direction of the napkin 1, and more preferably stretchability in the longitudinal direction and the width direction.
Further, the stretchable portion 31 of the back sheet remains after being stretched by 30% in the same direction as the longitudinal direction of the napkin (absorbent article), that is, stretched to a length of 1.3 times, and then contracted. The strain is preferably 10% or less, particularly 5% or less. Further, the strength at 30% elongation is preferably 80 cN / 10 mm or less, particularly 40 cN / 10 mm or less.
The non-stretchable portion 32 of the back sheet is preferably non-stretchable, but the non-stretchable portion 32 does not exclude a slightly stretchable material or a material with poor stretchability. Specifically, the strength of the napkin (absorbent article) when it is stretched by 10% in the longitudinal direction may exceed 100 cN / mm (preferably 200 cN / mm or more). In addition, it is preferable that the residual strain exceeds 10% when contracted after 30% elongation. In addition, when the napkin (absorbent article) is stretched 30% in the same direction as the longitudinal direction, it preferably has a yield point in the stress-strain curve in the 0-30% stretch range.

  The residual strain, the stress-strain curve, and the strength at 30% elongation can be determined as follows.

[Measurement method of residual strain]
A measuring piece having a length in the longitudinal direction of the napkin (absorbent article) of 100 mm and a length (direction in the width direction) perpendicular to the longitudinal direction of 10 mm from the measurement target part (stretchable part or non-stretchable part) of the back sheet (If the sample cannot be prepared with a predetermined size due to the restrictions on the size of the stretchable part or the non-stretchable part, it is changed as appropriate. The residual strain is considered not to depend on the width of the sample.) Tensile compression tester RTC-1210A (Toyo Orientech Co., Ltd.) was used to measure in the tensile mode. The measurement was performed on five measurement pieces, and the value at each of the upper and lower points was deleted, and the average value of the remaining three points was taken as the measurement value. The test piece is set between the air chucks attached to the tensile and compression tester with an initial sample length (distance between chucks) of 50 mm, and the chuck attached to the load cell (rated output 5 kg) of the tensile and compression tester is set at a speed of 300 mm / min. And the measurement piece was extended. When the measurement piece extended to 30% of the initial sample length, that is, 65 mm, the moving direction of the chuck was reversed, the chuck was lowered at a speed of 300 mm / min, and returned to the position of the initial sample length. During this operation, the relationship between the load detected by the load cell and the elongation of the measurement piece was recorded on a chart.
The residual strain is expressed by the following equation from the length (sample length after the test) when the load is recorded for the first time after the chuck is lowered from the maximum extension length (= 65 mm) and the initial sample length (= 50 mm). Obtained by (1).
Residual strain (%) = [(sample length after test−initial sample length) / initial sample length] × 100 (1)

[Stress-strain curve and strength measurement at 30% extension]
A measuring piece having a length in the longitudinal direction of the napkin (absorbent article) of 100 mm and a length (direction in the width direction) perpendicular to the longitudinal direction of 10 mm from the measurement target part (stretchable part or non-stretchable part) of the back sheet (If the sample cannot be prepared with the specified dimensions due to the dimensions of the stretchable part or non-stretchable part, it is changed as appropriate. The strength at 30% elongation is considered to be proportional to the width of the sample, and the width is less than 10 mm. If not, convert the measured value to a value per 10 mm.If the sample length is less than 100 mm, shorten the length appropriately and adjust the space between the air chucks.), Tension compression tester RTC-1210A (Toyo Orientech Co., Ltd.) Was measured in tension mode. The measurement was performed on five measurement pieces, and the value at each of the upper and lower points was deleted, and the average value of the remaining three points was taken as the measurement value. The test piece is set between the air chucks attached to the tensile and compression tester with an initial sample length (distance between chucks) of 50 mm, and the chuck attached to the load cell (rated output 5 kg) of the tensile and compression tester is set at a speed of 300 mm / min. And the measurement piece was extended. During this operation, the relationship between the load detected by the load cell and the elongation of the measurement piece was recorded on a chart to obtain a stress-strain curve. The load detected by the load cell when the measurement piece was 30% of the initial sample length, that is, 15 mm, was taken as the strength at 30% extension.

  “Having a yield point in the stress-strain curve in the 0-30% elongation range” means having a yield point in the range from the initial length to reaching the elongation rate of 30%. FIG. 9 shows an example of a stress-strain curve having a yield point at an elongation of about 7%. The yield point is a point at which a neck called necking passes through the elastic deformation region in the length direction of the test piece.

The non-stretchable portions 32 to 34 of the back sheet, particularly the non-stretchable portion 32 located in the center region in the width direction, have a strength at 10% elongation of 200 cN / 10 mm or more when stretched in the longitudinal direction of the napkin 1. It is preferable.
[Measurement method of strength at 10% elongation in the longitudinal direction]
A measurement piece having a length of 100 mm in the longitudinal direction of the napkin (absorbent article) and a length of 10 mm in the direction orthogonal to the longitudinal direction (width direction) is cut out from the non-stretchable part (with restrictions on the dimensions of the non-stretchable part). If the sample cannot be prepared with the specified dimensions, it is changed as appropriate.The strength at 10% elongation is considered to be proportional to the width of the sample, and if the width is less than 10 mm, the measured value is converted to a value per 10 mm, When the sample length was less than 100 mm, it was shortened as appropriate and the space between the air chucks was adjusted.), And the tensile compression tester RTC-1210A (Toyo Orientech Co., Ltd.) was used to measure in the tensile mode. The measurement was performed on five test pieces, the values at the upper and lower points were deleted, and the average value of the remaining three points was taken as the measured value. The test piece is set between the air chucks attached to the tensile and compression tester with an initial sample length (distance between chucks) of 50 mm, and the chuck attached to the load cell (rated output 5 kg) of the tensile and compression tester is set at a speed of 300 mm / min. And the measurement piece was extended. The load detected by the load cell when the measurement piece was 10% of the initial sample length, that is, 5 mm, was defined as the strength at the time of 10% elongation.

As described above, the napkin 1 of the present embodiment has the stretchable portion 31 of the back sheet 3 located at the left and right corners 1a, 1a on the front end side in the longitudinal direction of the napkin 1, so that the napkin 1 is being worn. The corners 1a and 1a are less likely to be twisted, and the corners 1a and 1a are relatively flexible, so that the wearer does not feel uncomfortable.
Furthermore, the napkin 1 according to the present embodiment further discomforts the wearer because the stretchable portions 31 of the back sheet 3 are located at the left and right corners 1b, 1b on the rear end side in the longitudinal direction of the napkin 1. It is difficult to give.
In addition, since the stretchable portions 31 are also located on both side portions 1c, 1c of the body portion 5 in the excretory portion facing portion C, particularly in the excretion portion facing portion C, the stretchable portion can be used even when the width of the napkin 1 is narrowed at the time of wearing. By contracting, the central portion of the napkin 1 is not swayed, so that stable absorption performance can be expressed, and there is an effect of reducing the uncomfortable feeling caused by rubbing the thigh.

  Like the napkin 1 of this embodiment, when the expansion-contraction part 31 of the back surface sheet 3 cuts through the excretion part opposing part C and extends in the longitudinal direction of the absorbent article, the expansion / contraction in the excretion part opposing part C The width W1 [see FIG. 1 (b)] of the portion 31 is preferably 10 to 20 mm. The width W1 of the stretchable part 31 is a width in the main body part 5 placed on the inner surface side of the shorts, and is a width from the non-stretchable part 32 to the outer edge of the main body part 5. Like the napkin 1 of this embodiment, the width W1 of the expansion / contraction part 31 in the case of having the wing parts 6 and 6 connects the rising base points before and after the wing parts 6 and 6 from the non-expansion / contraction part 32 in the central region. This is the distance to the straight line L6 (see FIG. 1B).

  Further, in the napkin 1 of the present embodiment, as shown in FIG. 2, the peripheral edge of the corner of the napkin 1 at any of the left and right corners 1a, 1a, 1b, 1b on the front end side and the rear end side of the napkin 1 The part 11 includes the stretchable part 31 of the back sheet 3 and the topsheet 2 laminated on the stretchable part 31 so as not to hinder the stretchability of the stretchable part 31. A corner peripheral part is a peripheral part of the absorbent article located in corner part 1a, 1a, 1b, 1b.

  2 and 3, the expansion / contraction part 31 and the surface sheet of the back sheet 3 at the corner peripheral part 11 of one corner 1a (the left corner 1a of FIG. 1B) on the front end side of the napkin 1 are shown. Although the joining aspect with 2 was shown, the back surface sheet 3 and the surface sheet 2 are joined by the same aspect also in the corner peripheral part 11 of other corner part 1a, 1b, 1b.

  As shown in FIG. 2, each corner peripheral portion 11 in the napkin 1 of the present embodiment is formed by the stretchable portion 31 and the top sheet 2 of the back sheet 3, and the back sheet in each corner peripheral portion 11. 3, the stretchable part 31 and the top sheet 2 are joined by intermittent joining in which the joining parts 12 and the non-joining parts 13 are alternately arranged in the longitudinal direction of the napkin 1 as shown in FIG. 3. The joint portion 12 where the stretchable portion 31 of the back sheet 3 and the top sheet 2 are joined can be formed by a known joining method such as heat sealing, ultrasonic sealing, or adhesive.

FIG. 4 is a diagram illustrating another preferable pattern of intermittent joining between the stretchable portion 31 of the back sheet 3 and the top sheet 2. FIG. 4 shows a bonding pattern in the corner peripheral edge 11 of the corner 1a. In the example shown in FIG. 4 (a), the joining portions 12 are formed in a dotted shape, and in the example shown in FIG. 4 (b), the joining portions 12 and the non-joining portions 13 are respectively the lengths of the napkin. They are alternately formed in a state slightly inclined with respect to the direction.
As shown in FIGS. 3 and 4, when intermittently joining in the longitudinal direction of the napkin 1, the length L <b> 12 of the joint portion 12 in the same direction and the non-joint portion 13 located between the joint portions 12, 12 are used. The ratio of the length L13 (L12 / L13) is preferably 0.5 to 20, particularly 1 to 10. Further, the length L13 of the non-joining portion 13 is preferably 1 to 10 mm, particularly 2 to 5 mm.

The stretchable part 31 and the topsheet 2 are joined by intermittent joining, so that the stretchability of the stretchable part 31 in the corner peripheral part 11 is not impaired.
By keeping the stretchability of the stretchable portion 31 in the corner peripheral edge portion 11 that is likely to hit the skin, the body, especially the thigh, the heel portion, the lower abdomen, and the napkin 1 are rubbed due to changes in posture and movement. It has the effect of suppressing waking and reducing wearer discomfort. In addition, it is possible to prevent the napkin 1 from being swung or displaced due to the movement of the body, and to exhibit a stable absorption performance.

  The non-stretchable portion 32 of the back sheet 3 is located in the center region in the width direction of the napkin 1, and the fastening portion 7 is provided on the non-stretchable portion 32. A rectangular portion 71 surrounded by a two-dot chain line in FIG. 1B is a range in which the fastening portion 7 is provided.

The napkin 1 has the non-stretchable portion 32 of the back sheet 3 in the center region in the width direction, so that the fastening portion 7 for fixing the main body portion 5 of the napkin 1 to clothing such as shorts is provided on the non-stretchable portion 32. Unlike the case where it is formed on the stretchable part of the back sheet, it is possible to prevent the inconvenience that the back sheet is stretched and the fastening part 7 is difficult to peel off from clothing such as shorts.
From the viewpoint of obtaining such an effect, the width W2 of the non-stretchable portion 32 of the back sheet 3 is preferably 30 to 50 mm. When the width W1 of the non-stretchable part 32 varies depending on the position in the longitudinal direction of the napkin (absorbent article), the width at the central part in the longitudinal direction of the excretory part facing part C is used as a reference.

Moreover, it is preferable that 60-100% of the area of the fastening part 7 provided in the main body part 5 is located on the non-stretchable part 32, and 80-100% of the area is non-stretchable part. It is more preferable that it is located on 32, and it is more preferable that 90 to 100% of the area is located on the non-stretchable part 32. Moreover, it is preferable that the width W3 [refer FIG.1 (b)] of the fixation part 7 is equivalent to the width W2 of the non-expandable-contraction part 32 (105% or less of W2), or this width W2 or less.
The fastening portion is not limited to a rectangle, and may be a combination of a plurality of rectangles, a stripe shape, an ellipse, other arbitrary shapes, and combinations thereof. FIG. 5 shows several examples of the formation mode of the fastening portion.

Further, the napkin 1 has the non-stretchable portion 32 of the back sheet 3 in the center region in the width direction, so that the dimensional stability in the flow direction when the napkin 1 is manufactured by the longitudinal flow method is improved, and the dimensional quality is improved. A homogeneous napkin 1 can be continuously produced efficiently. From such a viewpoint, the non-stretchable portion 32 in the napkin 1 of the present embodiment extends over substantially the entire length in the longitudinal direction of the napkin 1. The production method of the longitudinal flow method is a method of producing a napkin through a napkin continuous body having a shape in which the napkins are continuous in the longitudinal direction.
The non-stretchable part 32 has a length L1 measured along the longitudinal direction of the napkin 1 of preferably 80 to 100%, more preferably 90 to 100% of the total length L of the napkin 1. % Is more preferable.

  Further, the non-stretchable portions 33 and 33 of the back sheet 3 are respectively located on the wing portions 6 and 6 of the napkin 1. By having the non-stretchable part 33 in the wing part 6, the operation which folds and fixes the wing part 6 to the non-skin contact surface side of shorts becomes easy.

  In the peripheral part of the napkin 1 other than the corner peripheral part 11, the top sheet 2 and the back sheet 3 may be joined in the same manner as the corner peripheral part 11, or the top sheet 2 and the back face The sheet 3 may be bonded without causing a non-bonded portion by heat sealing or an adhesive.

  The material for forming each part of the napkin 1 will be described. As the center sheet 21, the side sheets 22, 22, the absorbent body 4, and the like, various materials conventionally used for absorbent articles such as sanitary napkins are conventionally used. It can be used without particular limitation. For example, as the central sheet 2, non-woven fabrics by various manufacturing methods, apertured films, laminates thereof, and the like can be used. As the side sheet 22, a water-repellent nonwoven fabric (thermal bond nonwoven fabric, spunbond nonwoven fabric, spunbond-meltblown-spunbond nonwoven fabric, spunbond-meltblown-meltblown-spunbond nonwoven fabric, etc.) or a laminate of a resin film and a nonwoven fabric Etc. can be used.

As the absorbent body 4, a fiber aggregate (may be a non-woven fabric) made of a fiber material such as pulp fiber, or a structure in which a superabsorbent polymer is held by tissue paper or a water-permeable non-woven fabric, An absorbent sheet manufactured by a wet papermaking method or a dry method can be used.
Moreover, the absorber which has a stretching property can also be used. As the stretchable absorber, various known ones can be used without particular limitation. For example, the one described in JP-A-2006-198396, the one described in the prior art of the gazette, etc. can be used. it can.

Further, as the absorber 4, a split type absorber composed of a large number of absorbing portions can be used. 6 and 7 are diagrams illustrating an example of a split-type absorber.
6 and 7, the absorption part 40 is a rectangular shape having a circular curve in a plan view, a rounded corner, and a gentle curve with four sides slightly convex outward. It has the shape of However, the shape of the absorber 40 in plan view is not limited to this. For example, the absorber 40 may have a square shape, a rectangular shape, or a rhombus shape in plan view. Further, two or more of these shapes may be combined.

  The absorption part 40 is arrange | positioned by the regular dot pattern over the plane direction. Specifically, the absorbers are arranged so as to form a first row 40A and a second row 40B in multiple rows that intersect each other. The surface of the back sheet 3 is exposed between the adjacent absorption parts. As a result, a space 42 including an exposed portion of the stretchable portion or the non-stretchable portion of the back sheet 3 is formed between the adjacent absorbing portions. The space 42 has a volume, width and / or height that allows the liquid in the absorbent body 4A to flow.

In the natural state (relaxed state), in the case of a sanitary napkin, each absorbent portion 40 has an area in a plan view of 10 to 900 mm ² , particularly 50 to 450 mm ² , so that both the stretchability and the absorption performance of the absorbent body are compatible. It is preferable from the point of making it. In addition, the thickness T of the absorbent body at the position where each absorbent portion exists is 0.4 to 10 mm, particularly 0.8 to 5 mm, in view of improving the wearing feeling of the absorbent article including the absorbent body and absorption. It is preferable from the viewpoint of lowering the rigidity of the body and adapting the absorbent article including the absorbent body and the back sheet to the wearer's body shape. Here, the thickness T of the absorbent body 4A does not include the thickness of the back sheet 3 to which the absorbent portion 40 is fixed. The absorber 40 is fixed to the stretchable part 31 or the non-stretchable part 32 of the back sheet 3 at a fixing point 43 formed by various known methods such as ultrasonic embossing.
In addition, the shape and area of each absorption part are not limited to the said dimension, For example, it can change suitably with absorbent articles, such as a diaper and urine picking pad for babies and adults.

  The distance D (see FIG. 7) between the adjacent absorption parts affects the volume of the space, and thus affects the fluidity of the liquid in the space. From this viewpoint, in the natural state (relaxed state), the distance D is preferably 0.2 to 5 mm, particularly preferably 0.5 to 3 mm. The distance D can be controlled by controlling the manufacturing conditions of the stretchable absorber described later. In addition, when paying attention to one absorption part, several other absorption parts 40 are located in the circumference | surroundings, and the distance D of the said one absorption part and the said other absorption part differs with the said other absorption part. In this case, the distance D when the distance D is the smallest is set as the distance between the adjacent absorbers.

  The constituent material of the absorbent portion is not particularly limited, and a fiber material, a porous body, a combination thereof, or the like can be used. Examples of fiber materials include natural fibers such as wood pulp, cotton and hemp, polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate, single fibers made of synthetic resins such as polyvinyl alcohol resin, and these resins. A composite fiber containing two or more kinds, or a semi-synthetic fiber such as acetate or rayon can be used. When using a fiber made of a synthetic resin, the fiber may be a heat-shrinkable fiber whose shape changes with heat. For example, the fineness is increased by heat but the fiber length is shortened, and the fineness is hardly changed by heat, but the apparent fiber occupies a short length by changing the shape to a coil shape. Also good. As the porous body, sponge, non-woven fabric, aggregate of superabsorbent polymer (aggregate of superabsorbent polymer and fiber) and the like can be used.

  As the pressure-sensitive adhesive for forming the fastening portion 7, various types conventionally used for absorbent articles such as sanitary napkins can be used without particular limitation. Further, the fastening portion is not limited to the adhesive, and a mechanical fastener may be used.

The absorbent article of the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit of the present invention.
For example, the joining state of the back sheet 3 and the top sheet 2 at the corners 1a and 1b on the front end side and / or the rear end side of the napkin 1 may be as shown in FIG.
In the embodiment shown in FIG. 8, the corner peripheral edge portion 11 is constituted by the stretchable portion 31 and the topsheet 2 of the backsheet 3, and the stretchable portion 31 and the topsheet 2 in the corner peripheral edge portion 11 are napkins. A predetermined range (for example, a range of 1 to 10 mm) from the peripheral edge 14 of the (absorbent article) is a non-joined portion 15 laminated in a non-joined state, and the non-joined portion 15 and the outer peripheral edge 41 of the absorbent body 4. Between the two, a joining portion 16 in which the back sheet 3 and the top sheet 2 are joined is formed. The joining portion 16 can be formed by a known joining method such as heat sealing, ultrasonic sealing, or adhesive.

  Also in the embodiment shown in FIG. 8, the stretchability of the stretchable portion 31 of the back sheet 3 is not easily impaired by having the non-joint portion 15 in the corner peripheral portion 11. As described above, the elasticity of the stretchable portion 31 at the corner peripheral edge portion 11 that is likely to hit the skin of the napkin 1 is not impaired, so that the body, particularly the thigh, the heel portion, the lower abdomen, and the napkin can be changed by posture change and movement. 1 has the effect of suppressing rubbing and reducing wearer discomfort. In addition, it is possible to prevent the napkin 1 from being shaken or displaced due to the movement of the body, and to express stable absorption performance. Further, the joint 16 can be expected to have an effect of suppressing the leakage of the liquid overflowing from the absorber 4 toward the peripheral edge 14 of the napkin 1.

Further, in the napkin 1 described above, the expansion / contraction portions 31 of the back sheet 3 are positioned at the left and right corners 1a, 1a, 1b, and 1b on the front end side and the rear end side of the napkin 1, respectively. The stretchable portion 31 of the back sheet 3 may be located only in any one of the left and right corners 1a, 1a and the left and right corners 1b, 1b on the rear end side. Moreover, although the napkin 1 mentioned above also has the non-expandable part 33 also in the back sheet 3 in the wing part 6, it may not have such a non-expandable part 33 and is located in the wing part 6. The whole area of the back sheet 3 to be formed may be formed of an expansion / contraction part. Moreover, although the napkin 1 mentioned above also has the non-stretchable part 34 also in the back surface sheet 3 in the rear flap part 8, you may not have such a non-stretchable part 34.
Further, in the napkin 1 described above, the top sheet 2 is a composite sheet composed of the center sheet 21 and the pair of side sheets 22, but instead, a surface composed of a single sheet having the same shape as the back sheet 3. A sheet can also be used.

  In addition to the sanitary napkin, the absorbent article of the present invention may be a panty liner (orimono sheet), an incontinence pad, or the like.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely using an Example, this invention is not restrict | limited at all by this Example.
[Example 1] First, as an elastomer resin, Toughmer 4050S (manufactured by Mitsui Chemicals, ethylene-butene-1 copolymer, density 0.863 g / cm ³ ) was extruded using a T-die to a basis weight of 20 g / m ^2. Molded to obtain an elastic film. Next, as a non-stretchable resin, Ultzex 2520F (linear low-density polyethylene, manufactured by Mitsui Chemicals, density 0.920, MI = 8) is extruded and molded so as to have a basis weight of 20 g / m ^2. An elastic film was obtained.
The two obtained films are overlapped with each other so that a non-stretchable sheet having a width of 40 mm-an elastomer sheet having a width of 25 mm-a non-stretchable sheet having a width of 75 mm-an elastomer sheet having a width of 25 mm-a non-stretchable sheet having a width of 40 mm Was heat sealed so as to be 3 mm to obtain a back sheet in which stretchable portions and non-stretchable portions were alternately arranged in the width direction.

The absorber was prepared according to the following method. 70 parts by weight of a cross-linked pulp (“High Bulk Additive HBA-S” manufactured by Weyerhauser) and 30 parts by weight of softwood kraft pulp (“Carib”) are dispersed and mixed in water, and the dry weight of the mixed pulp is 100 parts. 1 part by weight of a paper strength reinforcing agent (polyamide epichlorohydrin resin, manufactured by Seiko PMC Co., Ltd., Kaimen WS-570) is dispersed and mixed in water to obtain a predetermined concentration, and this dispersion mixture is wet-paper-made. A fiber web was formed in the forming part of the machine so that the dry basis weight was 25 g / m ² . Next, the fiber web was dehydrated with a suction box until the moisture content reached 100 parts by weight based on 100 parts by weight of the dry fiber web. Next, immediately before the press part, a water-absorbing polymer (manufactured by Nippon Shokubai Co., Ltd., CAW-151) was sprayed almost uniformly at a spraying basis weight of 50 g / m 2 on the wet fiber web after dehydration. Next, an absorbent paper (basis weight: 25 g / m2) having a blending composition similar to that of the fiber web as a fiber aggregate and having a composition similar to that of the fiber web is superimposed on the fiber web, and the fibers The laminated body of web and absorbent paper was introduced into a dryer, dried and integrated at a temperature of 130 ° C. to obtain an absorbent sheet having a water-absorbing polymer fixed therein. After the two absorbent sheets (length 90 mm, width 35 mm) are overlapped, the two absorbent sheets (length 200 mm, width 75 mm) are arranged above and below, and the longitudinal front and rear ends are curved. The absorbent was cut into a shape.

The top sheet was prepared as follows. First, a short fiber having a fiber length of 51 mm (core: polyethylene terephthalate, sheath: composite fiber made of high-density polyethylene, 2.1 dtex) is supplied to the card machine, and after creating a card web, heat treatment is performed by an air-through method. A nonwoven fabric of 30 g / m ² was obtained. The nonwoven fabric obtained was stretched in the longitudinal direction using a stretching apparatus equipped with a pair of concavo-convex rolls. As a result, a nonwoven fabric having a basis weight of 26 g / m ² extending in the longitudinal direction was obtained.

  An adhesive was applied to the non-skin contact surface side of the obtained absorbent body, and the back sheet center non-stretchable portion was fixed on the non-skin contact surface of the absorbent body via the adhesive. Next, the entire skin contact surface of the absorber is covered with the above surface sheet, and the skin contact surface side of the surface sheet is embossed according to a conventional method to form a leak-proof groove, and a napkin precursor Got the body. The adhesive part is formed by applying an adhesive to the non-skin contact surface of the napkin precursor thus obtained and the non-stretchable parts (the central part and the wing part of the napkin 1) of the outer surface of the back sheet. In each of the portions extending from the peripheral edge of the absorber (the back sheet corresponds to the elastomer portion), a dot-shaped end seal of 1.5 mm each (the interval between the dots is 1 mm, see FIG. 4A). To obtain a napkin.

[Example 2]
The back sheet of Example 1 was prepared by a multi-row extrusion method to obtain a back sheet. That is, using a single-screw extruder a as an extruder for a stretchable part composition and a single-screw extruder b as an extruder for a non-stretchable part, a per se known co-extrusion T die (each resin flow in a die lip) Linear low density polyethylene resin part having a width of 35 mm-Elastomer part having a width of 15 mm-Linear low density polyethylene resin part having a width of 75 mm-Elastomer part having a width of 25 mm-Linear low density polyethylene resin part having a width of 35 mm The basis weight of the obtained film was 25 g / m ² .

  The absorber was prepared as follows. The defibrated pulp (fluff pulp) 200 parts of fluff pulp and 50 parts of water-absorbing polymer were uniformly mixed in an air stream to obtain a pulp / water-absorbing polymer mixed fiber having a total basis weight of 250 g / m2. The obtained piled body was cut into a length of 15 mm and a width of 6 mm to obtain an absorbent body. Adjacent absorber bodies were arranged in a staggered manner with an interval in the width direction of 2 mm and an interval in the longitudinal direction of 5 mm. Except this, it carried out similarly to Example 1, and obtained the napkin.

Example 3
A napkin was obtained in the same manner as in Example 2 except that the elastomer resin of Example 2 was changed to Pentamax VM1100 (manufactured by ExxonMobil, ethylene-propylene copolymer, density 0.86 g / cm ³ ).

Example 4
First, an SMMS nonwoven fabric (spunbond-meltblown-meltblown-spunbond, manufactured by Mitsui Chemicals) having a basis weight of 13 g / m ² was prepared and cut into a width of 70 mm. The obtained SMMS nonwoven fabric was arranged at intervals of 20 mm, and the elastomer resin used in Example 3 was laminated so as to have a basis weight of 15 g / m ² to obtain a partially stretchable composite sheet. A napkin was obtained in the same manner as in Example 3 using the obtained composite sheet.

[Comparative Example 1]
A napkin was obtained in the same manner as in Example 1 except that a single film of linear low density polyethylene was used instead of the back sheet of Example 1.
[Comparative Example 2]
A napkin was obtained in the same manner as in Example 1 except that a single elastomer film was used instead of the back sheet of Example 1.

  Each of the napkins of Examples 1 to 4 had a flexible movement so as to follow the movement of the wearer, and had very little leakage of excrement from the crotch. In particular, in the case of Example 2, the followability at the crotch part is also high, and it moves like underwear, so that the uncomfortable feeling is further reduced and the liquid leakage during the wearer's operation is further reduced. On the other hand, in the case of the comparative example 1, it is lacking in flexibility, and in the case of the comparative example 2, it is likely that the crotch part tends to slip, and in that case, the excrement is likely to leak.

1A and 1B are diagrams showing a sanitary napkin as an embodiment of the present invention, in which FIG. 1A shows a state viewed from the top sheet side, and FIG. 1B shows a state viewed from the back sheet side. FIG. 2 is an enlarged schematic cross-sectional view taken along line II-II in FIG. FIG. 3 is a diagram illustrating a preferred example of intermittent joining between the stretchable portion of the back sheet and the top sheet. FIG. 4 is a diagram illustrating another preferred example of intermittent joining between the stretchable portion of the back sheet and the top sheet. FIG. 5 is a view showing a garment facing surface according to another embodiment of the present invention. FIG. 6 is a perspective view showing an example of a split-type absorber. FIG. 7 is a sectional view taken along line VII-VII in FIG. FIG. 8 is a diagram (corresponding to FIG. 2) showing another embodiment of the present invention. FIG. 9 is a diagram showing an example of a stress-strain curve having a yield point in the 0-30% elongation range.

Explanation of symbols

1 Sanitary napkin (absorbent article)
2 surface sheet 21 center sheet 22 side sheet 3 back sheet 31 stretchable part 32 non-stretchable part (non-stretchable part existing in the widthwise central region of the absorbent article)
33 Non-stretchable part (non-stretchable part in the wing part)
4,4A Absorber 40 Absorber 5 Body part 6 Wing part 7 Fastening part 8 Rear flap part C Excretion part opposing part 1a, 1b Corner part

Claims (6)

It has a top sheet that forms a skin facing surface, a back sheet that forms a clothing facing surface, and an absorber disposed between both sheets, and the back sheet is provided with a fastening portion for fixing to the clothing. An absorbent article,
The back sheet has a stretchable part and a non-stretchable part,
The stretchable part is located at the left and right corners on the front end side of the absorbent article, and the non-stretchable part is located in the center region in the width direction of the absorbent article,
An absorbent article, wherein the fastening part is provided on the non-stretchable part of the central region.   The absorbent article according to claim 1, wherein the stretchable part is also located at the left and right corners on the rear end side of the absorbent article.   The absorbent article according to claim 1 or 2, wherein the non-stretchable portion of the central region extends over substantially the entire length in the longitudinal direction of the absorbent article.   The peripheral edge portions of the absorbent article located at the left and right corners on the front end side and / or the rear end side are stretched so that the stretchable part of the back sheet and the stretchability of the stretchable part are not hindered. The absorbent article in any one of Claims 1-3 which consists of the said surface sheet laminated | stacked on the part.   The absorptive article according to claim 4 in which said elastic part and said surface sheet which form said corner part peripheral part are joined by intermittent joining.   The stretchable part and the top sheet that form the corner peripheral part are non-joined parts laminated in a non-joined state within a predetermined range from the peripheral edge of the absorbent article, and the non-joint part and the absorber The absorptive article according to claim 4 in which the joined part by which said back sheet and said surface sheet were joined is formed between the outer periphery.

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