JP6458176B2 - Absorbent articles - Google Patents

Description

  The present invention mainly relates to absorbent articles used for sanitary napkins, vaginal sheets, incontinence pads, medical pads, toiletries, etc., even when the absorbent body is relatively thin and hard, It is related with the absorbent article which reduced the sense of incongruity.

  Conventionally, as an absorbent article 50 such as a panty liner, sanitary napkin, or incontinence pad, as shown in FIG. 8, a liquid-impervious back sheet 51 such as a polyethylene sheet or a polyethylene sheet-laminated nonwoven fabric, and a nonwoven fabric or a liquid-permeable material There is known one in which an absorbent body 53 made of cotton-like pulp or the like is interposed between a liquid-permeable surface sheet 52 such as a conductive plastic sheet. The absorbent body 53 is generally formed into a generally oval planar shape as a whole by forming the front shape line and the rear shape line in an arc shape that bulges outward.

  In recent years, in the case of relatively bulky absorbent articles, there are problems such as inconvenience to carry or poor storage properties, and the thickness of the absorbent body has been increased due to demands for efficient logistics and resource saving. However, thin absorbent articles having a thickness of about 3 mm or less tend to be preferred. When thinning an absorbent article, the water absorption cannot be reduced even if it is thinned or made compact. Therefore, the content of the superabsorbent resin is inevitably increased or a polymer sheet is used. At the same time, thinning is often performed by applying a severe press to the absorber.

  However, in an absorbent article using such a thin absorbent body, the density of the pulp is increased and the absorbent body becomes hard, which gives the wearer a sense of discomfort and discomfort at the time of wearing. In particular, when the front and rear ends of the absorbent body hit the body, there may be a sense of incongruity or discomfort such as a tingling sensation that pierces the skin or a rubbing feeling that rubs against the skin.

  In the following Patent Document 1, by disposing a nonwoven fabric between the liquid-permeable surface sheet and the absorbent body and between the liquid-impermeable back sheet and the absorbent body, the skin surface and the side surface when worn by the nonwoven fabric. On the other hand, an absorbent article that gives flexibility and cushioning properties and has a good wearing feeling is disclosed.

  Further, in Patent Document 2 below, the absorbent body is composed of a plurality of absorbent sheets sequentially connected in the longitudinal direction, and the plurality of absorbent sheets are overlapped with each other in the longitudinal direction at the side ends thereof. An absorbent article that is formed and prevents discomfort and discomfort at the time of wearing is disclosed by providing a fixing portion that connects the sheets to each other in the widthwise central portion of the absorbent sheet in the overlapping portion. Yes.

JP 2003-275240 A JP 2009-153838 A

  However, in the absorbent article described in Patent Documents 1 and 2, since another member is laminated on the absorbent body or the end portions of a plurality of absorbent sheets are overlapped, the overall thickness is increased accordingly. Thus, the advantages of the thin absorbent article were impaired.

  In addition, the conventional thin absorbent article is formed to be harder than a normal absorbent body and has a substantially oval planar shape as described above. Was given. In particular, when the absorber is deformed so that the central portion in the width direction of the absorber is recessed toward the skin along the buttock groove, the tip of the bent portion is bent so that the tip is sharp on the skin. It was pierced and increased discomfort and discomfort when worn.

  Therefore, a main problem of the present invention is to provide an absorbent article that reduces the uncomfortable feeling and discomfort at the time of wearing even when the absorbent article is a relatively thin and hard thin absorbent article.

In order to solve the above problems, as the present invention according to claim 1, in an absorbent article in which an absorber is interposed between a liquid-permeable top sheet and a back sheet,
The absorber is formed in a wave shape in which convex portions and concave portions each having at least a rear shape line formed by a curve in which a slope of a tangent continuously changes, and the rear shape line is an absorber. A concave portion is formed in the central portion in the width direction, and two or more convex portions are formed on both sides thereof, and the concave portion is formed between the convex portions.
An absorbent article is provided in which slits are provided inward from the tops of both the convex part and the concave part of the rear side shape line .

In the invention of claim 1, by forming at least the rear shape line of the absorber in a wavy shape in which convex portions and concave portions constituted by curves in which the slope of a tangent continuously changes are formed, In the case of a thin and thin absorbent article in which the absorber is relatively thin and hard because the rear end of the absorber is easily deformed along the convex and concave portions of the shape line and is easy to follow the roundness of the body when worn. However, it is possible to reduce discomfort and discomfort when the rear end touches the skin during wearing.

Further, the rear shape line has a wavy shape in which a concave portion is formed in the central portion in the width direction of the absorber, two or more convex portions are formed on both sides thereof, and a concave portion is formed between the convex portions. It is said.

  By forming the rear shape line so that the central portion in the width direction of the absorber becomes a concave portion, when the rear side of the absorber is deformed along the buttocks groove, that is, the central portion in the width direction of the absorber is on the skin side. When bent so as to protrude, compared to the case where the rear shape line of the absorbent body is formed by an arc or the like, a sharp tip is less likely to be formed at the rear edge of the absorbent body, which pierces the skin and feels strange when worn And less discomfort.

Furthermore, the slit inwardly from the top of both the peaks and valleys of the rear shaped line that provided.

On the side shape lines after being formed in a wave shape consisting of peaks and valleys, for each from the top of both the peaks and valleys are the slits provided inward, the ends of the absorber by flexibly deformed It becomes easier to follow the body, and discomfort and discomfort when hitting the skin at the time of wearing can be further reduced.

As the present invention according to claim 2, wherein the slits, the absorbent article according to claim 1, wherein formed in the intermittent straight line shape is provided.

In the second aspect of the invention, when the slit is provided inward from the top of the convex portion and the concave portion of the rear shape line, the slit is formed in an intermittent linear shape. The intermittent linear form is one in which cut portions and non-cut portions are alternately and repeatedly provided along the slit. As a result, the end of the absorber can be flexibly deformed without losing the absorber.

As the present invention according to claim 3, wherein the absorbent body, any claim 1, 2 is better in the vicinity of the wave which is formed in the shape line of the longitudinal end portion than the front-rear direction central portion is formed at a lower basis weight An absorbent article as described above is provided.

In the invention of claim 3 , as the absorber, a shape formed in a wavy shape by lowering the basis weight in the vicinity of the wavy shape line at the front-rear direction end than in the front-rear center. The line is hard to harden, and the discomfort and discomfort when hitting the skin at the time of wearing can be further reduced.

As the present invention according to a fourth aspect , there is provided the absorbent article according to any one of the first to third aspects, wherein the absorbent body has a front shape line formed in a wave shape.

In the invention of claim 4 , the front shape line of the absorber is also formed in a wave shape, so that it is possible to reduce discomfort and discomfort when the front end hits the lower abdomen during wearing.

  As described above in detail, according to the present invention, even when the absorbent body is a relatively thin and hard thin absorbent article, it is possible to reduce discomfort and discomfort during wearing.

It is a partial fracture development view of sanitary napkin 1 concerning the present invention. It is the II-II arrow directional view. It is a top view of absorber 4 concerning a modification. It is a top view of the absorber 4 in which the slit 15 was formed. (A), (B) is the principal part enlarged view of the absorber 4 in which the slit 15 was formed. It is a principal part enlarged view of the absorber which formed the undesirable form slit. 4 is a plan view of the absorber 4. FIG. It is a partially broken developed view of a conventional absorbent article 50.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Basic structure of sanitary napkin 1]
As shown in FIGS. 1 and 2, the sanitary napkin 1 according to the present invention has a liquid-impervious back sheet 2 made of a polyethylene sheet, a polypropylene sheet, and the like, and a liquid-permeable material that allows menstrual blood, cages, and the like to pass therethrough. It is mainly composed of a top sheet 3 and an absorbent body 4 made of cotton-like pulp or synthetic pulp interposed between the two sheets 2 and 3.

Hereinafter, the structure of the sanitary napkin 1 will be described in detail.
As the liquid-impermeable back sheet 2, a sheet material having at least water shielding properties such as an olefin resin sheet such as polyethylene or polypropylene is used. In addition, a laminated nonwoven fabric obtained by laminating a nonwoven fabric on a polyethylene sheet or the like, or A nonwoven fabric sheet (in this case, the waterproof film and the nonwoven fabric constitute a liquid-impervious back sheet) can be used after substantially impervious to liquid imperviousness by interposing a waterproof film. In recent years, those having moisture permeability tend to be used from the viewpoint of preventing stuffiness. This water- and moisture-permeable sheet material is a microporous sheet obtained by forming a sheet by melting and kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene, and then stretching in a uniaxial or biaxial direction. It is.

  Next, as the liquid-permeable surface sheet 3, a porous or non-porous nonwoven fabric or a porous plastic sheet is preferably used. Examples of the material fibers constituting the nonwoven fabric include synthetic fibers such as polyethylene or polypropylene, synthetic fibers such as polyester and polyamide, recycled fibers such as rayon and cupra, and natural fibers such as cotton. A nonwoven fabric obtained by an appropriate processing method such as a lace method, a spun bond method, a thermal bond method, an air through method, a melt blown method, or a needle punch method can be used. Of these processing methods, the spunlace method is excellent in terms of flexibility and the spunbond method is excellent in drapeability, and the thermal bond method and the air-through method are excellent in terms of being bulky and soft.

  The absorbent body 4 interposed between the liquid-impervious back sheet 2 and the liquid-permeable top sheet 3 is, for example, a mixture of a superabsorbent resin in pulp or a mixture of chemical fibers in the pulp. A high water-absorbing polymer is used. The absorbent body 4 can be surrounded by a crepe paper 5 or the like as shown in the illustrated example in order to maintain the shape and quickly diffuse menstrual blood and prevent reversal of once absorbed menstrual blood and the like. Yes or no. The absorber 4 will be described in detail later.

In particular, when the thin sanitary napkin 1 is used as in the present invention, the absorber 4 is thinned by pressing. The thickness of the absorber 4 is approximately 2.5 mm or less, preferably 2 mm or less. The physical property values after press working are such that the density is 0.07 g / cm ³ or more and the WC value (compression energy) by a KES compression tester is less than 0.8 gf · cm / cm ^2. Is desirable. The KES compression tester (manufactured by Kato Tech Co., Ltd.) is a tester for simulating the sensation of touching an object with a human fingertip, and measures compression energy, compression hardness, compression recovery, etc. Is possible. The measurement is performed by compressing the sample under the conditions of speed: 0.1 cm / sec, compression area: 2 cm ² , sensitivity: 2 (force meter 200 g / 10 v), compression load: 50 gf / cm ² , and a correlation diagram between pressure and deformation. LC (compression hardness), WC (compression energy), and RC (compression recoverability) are calculated.

Examples of the pulp include chemical fibers obtained from wood, cellulose fibers such as molten pulp, and those made of artificial cellulose fibers such as rayon and acetate. It is preferably used in terms of price. As the absorbent body 4, one prepared by pile fiber or airlaid method can be used. In particular, in order to reduce the hardness and soften the skin, it is preferable to use one made by stacking fibers. The basis weight of the piled pulp can be 120 to 320 g / m ^2, and may be a uniform basis weight over the entire absorbent body. It may be formed. Moreover, as the superabsorbent polymer, superabsorbent polymer granular powder (SAP) or superabsorbent polymer fiber (SAF) can be used, and the basis weight is preferably 30 to 120 g / m ² .

  In the assembled state of the sanitary napkin 1 in which the absorbent body 4 is interposed between the liquid-permeable top sheet 3 and the liquid-impervious back sheet 2, the thin sanitary product has a thickness of 1 to 3 mm, preferably 1 to 2 mm. A napkin is recommended.

[About absorber 4]
The absorbent body 4 will be described in more detail. As shown in FIG. 1, the absorbent body 4 is a rear side extending substantially in the width direction on the rear side (buttock side) and the front side (lower abdomen side) of the napkin front and rear direction. A shape line is formed by the shape line 10 and the front side shape line 11 and side shape lines 12 and 12 extending substantially in the front-rear direction on both sides in the napkin width direction. The side shape line 12 may be a straight line with respect to the napkin front-rear direction, or may be a curved line that bulges inward to soften the contact with the crotch part.

  As shown in FIG. 1, the absorber 4 has at least the rear shape line 10 formed in a wave shape. “Wavy” in the present invention means that convex portions 13 and concave portions 14 formed by curves in which the slope of a tangent continuously changes are alternately formed, and include irregularities due to straight lines such as rectangular waves and triangular waves. Make it not exist. Further, in the rear shape line 10, one or more convex portions 13 and concave portions 14 are formed, and at least one of the convex portions 13 or the concave portions 14 is formed two or more.

  More specifically, the rear shape line 10 is formed in a wave shape along a virtual arc that bulges outward. That is, the rear shape line 10 is a wavy line composed of a convex portion and a concave portion on a virtual arc line that bulges outward on the center side in the longitudinal direction of the absorber 4 and having a center of curvature in the center portion in the width direction. It is formed by overlapping.

  By forming the rear shape line 10 in a wavy shape, the rear end portion of the absorber 4 is easily deformed along the convex portion 13 and the concave portion 14 of the shape line at the time of wearing, and becomes easier to follow along the body. Even when 4 is relatively thin and hard, it is possible to reduce discomfort and discomfort during wearing.

  The rear shape line 10 is preferably formed in a wave shape such that the concave portion 14 is located in the center portion in the width direction of the absorber 4. Thereby, when the rear side of the absorbent body 4 is deformed along the buttock groove, that is, when the center of the absorbent body 4 is bent so as to protrude to the skin side, the tip sharpened by the rear side edge of the absorbent body 4 It is difficult to form a portion, and the problem that this pierces the skin and gives a sense of incongruity or discomfort at the time of wearing is less likely to occur.

  As shown in FIG. 1, the rear shape line 10 has a concave portion 14 formed at the center in the width direction of the absorber 4, and two or more convex portions 13 are formed on both sides thereof. It is preferable to use a wave shape in which a recess 14 is formed between the portions 13 and 13. When the wavy irregularities are finely formed in this way, the end portions in the front-rear direction of the absorbent body 4 are easily deformed flexibly and easily along the irregularities of the body. In this case, since the wavy line is formed along the virtual arc that bulges outward as described above, the convex portion 13 on the center side in the width direction is formed on the outer side than the convex portion 13 on the outer side in the width direction. It becomes like this. For this reason, when the rear side of the absorbent body 4 is bent so that the central part in the width direction protrudes to the skin side along the buttock groove at the time of wearing, it becomes easy to fit along the roundness of the buttock.

  The curvature radius R of the convex portion 13 and the concave portion 14 is 10 mm to 20 mm, preferably 10 mm to 15 mm. By setting it as R10 or more, the contact with the skin becomes soft and it becomes easy to follow along with the body, so that uncomfortable feeling and discomfort at the time of wearing can be surely reduced.

  In the example shown in FIG. 1, the rear shape line 10 and the front shape line 11 are each formed in a wave shape. Forming the front shape line 11 in a wavy shape is preferable because it can reduce a sense of discomfort and discomfort when the front end hits the lower abdomen when worn. The wavy lines of the rear shape line 10 and the front shape line 11 may be the same shape or different shapes.

  On the other hand, as shown in FIG. 3, the absorber 4 can be formed by an arc that forms only the rear shape line 10 in a wavy shape and bulges the front shape line 11 outward. By forming at least the rear shape line in a wavy shape, it is possible to improve the wearability at the buttocks.

  As shown in FIG. 4, the slits 15 can be provided inwardly from the tops of either or both of the convex portions 13 and the concave portions 14 of the wavy line. The slit 15 is a cut portion in which the absorbent fibers are discontinuous from the skin side surface to the non-skin side surface of the absorbent body 4. The top is the portion that is furthest away from the center line of the wavy line to the outside and the inside. When the wavy line is superimposed on the virtual arc line as described above, it is the furthest away from the arc line to the outside and the inside. It is a part to do. The slit 15 is formed on a straight line that is substantially orthogonal to the tops of the convex portion 13 and the concave portion 14. By providing the slit 15, the end of the absorber 4 is deformed supple and becomes easy to follow along with the body, and it is possible to further reduce discomfort and discomfort when hitting the skin during wearing.

  As shown in FIG. 5, the slit 15 includes (A) an intermittent linear shape in which cut portions 15a and non-cut portions 15b are alternately provided along the slit 15, and (B) a continuous linear shape. Can be formed. Among these, when it is provided in an intermittent linear shape, the rigidity of the absorber 4 can be reduced without the absorber 4 being divided, which is particularly preferable. On the other hand, as shown in FIG. 6, it is not preferable to form a V-shaped slit in which both side walls of the cut portion are separated because the absorber 4 is easily lost.

  As shown in FIG. 4, the slit 15 has a length extending from the inner end of the absorber 4 to the arc line 16 having the center of curvature at the center in the longitudinal direction of the absorber 4 and at the center in the width direction. It is preferable to form it. The arc line 16 is preferably formed to be substantially equivalent to a virtual arc that is a base obtained by superposing wavy lines of the shape lines of the front and rear end portions of the absorber 4. By aligning the base end portion of the slit 15 with the arc line 16, the divided portions of the absorbent body 4 are formed with substantially equal lengths at the front and rear end portions of the absorbent body 4, and the softness per skin acts substantially equally. To come.

As shown in FIG. 7, the absorbent body 4 has a center area 17A when the basis weight of the central area 17A in the front-rear direction is Agsm and the basis area of the end area 17B near the wavy shape line is Bgsm. The end regions 17B and 17B are preferably formed with a lower basis weight (Agsm> Bgsm). Thereby, the feel of the front and rear end portions is softened, and the front and rear end portions are not easily hardened by the compressive force of the cutter during cutting. The weight Agsm of the central region 17A is 150 to 320 g / m ² , preferably 230 to 320 g / m ² . The weight Bgsm of the end region 17B is 120 to 260 g / m ² , preferably 120 to 200 g / m ² . The vicinity of the wavy shape line described above refers to a range within 15 mm, preferably within 7 mm, from the rear shape line 10 and the front shape line 11 formed in a wave shape.

  DESCRIPTION OF SYMBOLS 1 ... Sanitary napkin, 2 ... Impervious back sheet, 3 ... Impervious surface sheet, 4 ... Absorber, 5 ... Crepe paper, 10 ... Rear shape line, 11 ... Front shape line, 12 ... Side part Shape line, 13 ... convex part, 14 ... concave part, 15 ... slit

Claims (4)

In the absorbent article in which an absorbent body is interposed between the liquid-permeable top sheet and the back sheet,
The absorber is formed in a wave shape in which convex portions and concave portions each having at least a rear shape line formed by a curve in which a slope of a tangent continuously changes, and the rear shape line is an absorber. A concave portion is formed in the central portion in the width direction, and two or more convex portions are formed on both sides thereof, and the concave portion is formed between the convex portions.
An absorptive article, wherein a slit is provided inward from the top of both the convex part and the concave part of the rear shape line . The slit absorbent article of claim 1 wherein the formed intermittently in a straight line. The absorbent article according to any one of claims 1 and 2 , wherein the absorbent body is formed with a lower basis weight in the vicinity of a wavy shape line at an end portion in the front-rear direction than in a center portion in the front-rear direction. The absorbent article according to any one of claims 1 to 3 , wherein the absorbent body has a front shape line formed in a wave shape.

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