ABSORBENT ARTICLE
20200246200 ยท 2020-08-06
Inventors
Cpc classification
A61F13/514
HUMAN NECESSITIES
A61F2013/51338
HUMAN NECESSITIES
A61F2013/51165
HUMAN NECESSITIES
International classification
A61F13/511
HUMAN NECESSITIES
Abstract
On a skin side surface of a liquid permeable top sheet (3), embossed portions (10, 10, . . . ) depressed toward a non-skin side are arranged at intervals. Each embossed portion (10) is formed in a planar shape passing through each corner (12) of an original shape (11) and having concave shaped outlines (14) each formed by a curve bulging each side (13) of the original shape toward the center. A quadrangle having four or more sides is defined as the original shape (11). Because liquid intensive regions (15) formed along a periphery of the embossed portion (10) are separated at a central portion, the liquid intensive regions (15) become less noticeable. Also, a perimeter is increased by the concave shaped outlines (14) while a compressed area is reduced, the body fluid is dispersed and a color of the body fluid becomes less noticeable without deteriorating the touch feeling.
Claims
1. An absorbent article, in which an absorbent body is interposed between a liquid permeable top sheet and a liquid impermeable back sheet, the absorbent article comprising: a plurality of embossed portions arranged at intervals on a skin side surface of the liquid permeable top sheet, each embossed portion recessed on a non-skin side, wherein each embossed portion is formed in a planar shape passing through each corner of an original shape, having concave outlines each formed by a curve passing through respective corners of the original shape, and bulging each side of the original shape toward a center, in which a polygon having four or more sides is defined as the original shape.
2. The absorbent article as claimed in claim 1, wherein the original shape is formed by a square.
3. The absorbent article as claimed in claim 1, wherein each of sides of the original shape is 2-20 mm in length.
4. The absorbent article as claimed in claim 1, wherein adjacent embossed portions are arranged so that corners of the original shape face each other.
5. The absorbent article as claimed in claim 1, wherein a size of each embossed portion is larger than an interval between adjacent embossed portions.
6. The absorbent article as claimed in claim 1, wherein an interval between adjacent embossed portions is 2 to 20 mm.
7. The absorbent article as claimed in claim 1, wherein ends of the outlines extending to respective corners of the original shape are intersected or are chamfered in a curved line or a straight line.
8. The absorbent article as claimed in claim 1, wherein at least an inside of a circle with a diameter of 1 mm inscribed in each of the embossed portions is squeezed.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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[0043]
MODE FOR CARRYING OUT THE INVENTION
[0044] In the following, embodiments of the present invention are described below with reference to the accompanying drawings.
Basic Constitution of Sanitary Napkin 1
[0045] As described in
[0046] The structure of the sanitary napkin 1 will be described in detail below.
[0047] For the liquid impermeable back sheet 2, a sheet material having at least a water-shielding property such as an olefin-based resin sheet such as polyethylene or polypropylene is used; alternatively, a laminated non-woven fabric sheet, in which a non-woven fabric is laminated on a polyethylene sheet or the like; furthermore, a non-woven fabric sheet or the like may be used by interposing a waterproof film to substantially ensure liquid impermeability (in this case, a liquid permeable top sheet is formed by a waterproof film and non-woven fabric). In recent years, moisture permeability tends to be used from a viewpoint of prevention of stuffiness. This moisture permeable sheet material is a microporous sheet, which is obtained by stretching a sheet in an uniaxial or biaxial direction after the sheet is formed by melt-kneading an inorganic filler in an olefinic resin such as polyethylene or polypropylene.
[0048] A non-woven fabric is preferably used for the liquid permeable top sheet 3. As the material fiber forming the non-woven fabric, for example, synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, polyamides, the like, recycled fibers such as rayon and cupra, and natural fibers such as cotton may be used, and a non-woven fabric, which is obtained by a suitable processing method such as a spun lace method, a spun bonding method, a thermal bonding method, a melt-blown method, a needle punching method, may be used. Among these processing methods, the spun lace method is excellent in flexibility, the spun bonding method is excellent in drapeability, and the thermal bond method and the air-through method are excellent in that they are bulky and have high compression restorability. Also, composite fibers, such as core-sheath type fibers with high melting point fiber as core and low melting point fiber as sheath, side-by-side type fibers and split type fibers, may be used. In order to achieve with a side sheet 7, it is preferable to mix synthetic fibers for the liquid permeable top sheet 3.
[0049] As the absorbent body 4, which is interposed between the liquid impermeable back sheet 2 and the liquid permeable top sheet 3, for example, a material obtained by mixing a highly water-absorbing resin into pulp or a material obtained by mixing a chemical fiber into a pulp and also mixing a highly water-absorbing resin is used. As depicted in the figure, it is desirable that the absorbent body 4 is surrounded by the wrapping sheet 5 in order to maintain the shape and quickly diffuse menstrual blood and the like, and prevent the menstrual blood and the like once absorbed from returning. Examples of the pulp include those made of cellulose fibers such as chemical pulp and molten pulp obtained from wood, and artificial cellulose fibers such as rayon and acetate; and softwood pulp having a longer fiber length than hardwood pulp is more preferably used in terms of function and price. Moreover, as the absorbent body 4, an air-laid absorbent body whose bulk may be reduced, or a polymer sheet, in which a superabsorbent resin is arranged between two non-woven fabric layers, may be used.
[0050] Also, synthetic fibers may be mixed in the absorbent body 4. For the synthetic fibers, for example, polyolefins such as polyethylene or polypropylene, polyesters such as polyethylene terephthalate or polybutylene terephthalate, polyamides such as nylon, and copolymers thereof, and the like may be used, and a mixture of these two types may be used. Moreover, composite fibers such as a core-sheath type fiber having a high melting point fiber as a core and a low melting point fiber as a sheath, a side-by-side type fiber, and a split type fiber, or the like may be used. As the synthetic fiber, in a case of a hydrophobic fiber, it is desirable to use a surface-treated synthetic fiber having a hydrophilicity agent so as to have an affinity for a body fluid.
[0051] Examples of the superabsorbent resin include a crosslinked product of polyacrylate, a crosslinked product of self-crosslinked polyacrylate, a saponified product of a crosslinked product of an acrylate-vinyl acetate copolymer, a crosslinked product of an isobutylene/maleic anhydride copolymer, cross-linked polysulfonate, partially crosslinked water-swellable polymers such as polyethylene oxide and polyacrylamide, and the like. Among these examples, acrylic acid or acrylate-based compounds having an excellent water absorption and an excellent water absorption speed are preferred. In a production process of a superabsorbent resin having the water absorbing performance, a water absorbing ability and the water absorbing speed are able to be adjusted by adjusting a crosslinking density and a crosslinking density gradient.
[0052] In a case in which the wrapping sheet 5 surrounding the absorbent body 4 is provided as in these examples, the wrapping sheet 5 is interposed between the liquid permeable top sheet 3 and the absorbent body 4 as a result. In a case in which the wrapping sheet 5 is made of crepe paper, the wrapping sheet 5 having excellent absorptivity allows the body fluid to be quickly diffused and prevents the menstrual blood from returning.
[0053] The second sheet 6 may be any kind as long as it has hydrophilicity to body fluids. Specifically, a material itself including hydrophilicity may be used by using regenerated fibers such as rayon and cupra, and natural fibers such as cotton; alternatively, a fiber, which has hydrophilic property imparted by surface-treating a synthetic fiber such as olefins such as polyethylene or polypropylene, polyesters, polyamides, or the like with a hydrophilic agent, may be used. In addition, the second sheet 6 may have a porous film layer on a back surface side (absorbent body 4) in order to have a firmness, may be a laminated sheet with an enveloped sheet, and further may be a material containing pulp.
[0054] On both sides of the sanitary napkin 1 on the skin contact surface side, side sheets 7, 7 are respectively provided along a longitudinal direction and over substantially the entire length of the napkin 1, side sheets 7, 7 are extended laterally, and the liquid impermeable back sheet 2 also extended laterally, whereby flap portions are formed on both sides of a main body portion where the absorbent body 4 is not interposed. Wing-shaped flaps W, W protruding outward are formed by parts of the side sheets 7 and parts of the liquid impermeable back sheet 2, which extend laterally. The wing-shaped flaps W, W are used by being folded outward at a fold line RL (
[0055] As the side sheets 7, a water-repellent non-woven fabric or a hydrophilic non-woven fabric may be used from a viewpoint of a function regarded as important. For example, if emphasis is placed on functions such as preventing menstrual blood or vaginal discharge from penetrating or enhancing the feel of the skin, it is desirable to use a water-repellent non-woven fabric coated with a silicon-based, paraffin-based, alkylchromic chloride-based water-repellent, or the like. Also, if emphasis is placed on the absorbability of menstrual blood and the like in the wing-shaped flaps W, W, it is desirable to use a hydrophilically-treated nonwoven fabric that has been rendered hydrophilic by applying capillary action, which the synthetic fibers are made to be swollen or porous by a method of polymerizing in the presence of a compound having a hydrophilic group, for example, an oxidation product of polyethylene glycol or the like in the process of producing a synthetic fiber, a method of treating with a metal salt such as stannic chloride, partially dissolving a surface to form porous and depositing a metal hydroxide. It is preferable that a synthetic fiber is blended in the side sheets 7 in order to achieve fusion with the liquid permeable top sheet 3.
Embossed Portions 10
[0056] As depicted in
[0057] As depicted in
[0058] The original shape 11 is represented by a virtual figure used to draw each of the embossed portions 10 and is not arranged on an actual sanitary napkin 1 as depicted in
[0059] In each of the embossed portions 10, a region (shaded region depicted in
[0060] The embossed portion 10 is formed, in which a total length (perimeter) of the outlines 14, 14, . . . is formed longer than a total length (perimeter) of sides 13, 13, . . . of the original shape 11, and an area is smaller than an area of the original shape 11.
[0061] Because the plurality of the embossed portions 10 are formed at intervals in the sanitary napkin 1, as depicted in
[0062] Also, because each of the embossed portions 10 is formed in the planar shape having concave shaped outlines 14 shaping curves each obtained by bulging each side 13 of the original shape 11 toward the center, in which a polygon having the number of four or more sides is defined as the original shape 11 and passes through each corner 12 of the original shape 11, as depicted in
[0063] Also, because as compared with the original shape 11, each perimeter of the embossed portions 10 is increased by the concave shaped outlines 14 bulging toward the center of the original shape 11 while reducing a compressed area (seal area), the amount of the body fluid contained per unit length of the liquid intensive region 15 is able to be reduced, and an effect of dispersing the body fluid makes a color of the body fluid less visible in appearance.
[0064] Moreover, each of the embossed portions 10 is formed in a planar shape having a concave shaped outline 14 formed by a curve obtained by bulging each side 13 of the original shape 11 toward the center, the compressed area (seal area) of the embossed portion 10 is reduced so that it is possible to prevent the touch feeling from becoming worse, as compared with a case in which the original shape 11 is compressed to form the embossed portion.
[0065] Furthermore, because each of the outlines 14 of the embossed portion 10 is formed in a concave shape forming a curve, it is difficult to form a bending base point of the liquid permeable top sheet 3 on the outline 14, and it is possible to prevent the touch feeling from being deteriorated.
[0066] Also, By forming the outline 14 by a curve, if a maximum separation distance (depth of bulging toward the center side) from the original shape 11 is the same, forming with a curve is able to make an outline longer than forming with a broken line (straight line), the liquid intensive region 15 becomes less noticeable in appearance.
[0067] Each of the outlines 14 of the embossed portion 10 is preferably formed by a curve bulging toward the center of the original shape 11, particularly an arc. The arc is a part of a circumference formed with a constant radius. It is preferable that each outline 14 and each side 13 have a maximum separation width at the central portion, and are formed so that the separation width gradually decreases toward both ends (corners 12). Each of the outlines 14, 14, . . . is extended between adjacent corners 12, 12 of the original shape 11 without intersecting each other.
[0068] In a case in which the original shape 11 is a rhombus obtained by rotating a regular square by 45 degrees with respect to the longitudinal direction of the sanitary napkin 1, and the outline 14 is the arc as depicted in
[0069] In particular, it is desirable that the original shape 11 is formed in a quadrangle. By making the original shape 11 the quadrangle, the planar shape of the embossed portion 10 becomes a substantially cross shape and as depicted in
[0070] As depicted in
[0071] In a case in which the outline 14 is formed by an arc, a radius of the arc is preferably 1 to 20 mm, particularly preferably 3 to 10 mm. In a case in which the radius of the arc is smaller than 1 mm, a plurality of liquid intensive regions 15 may be conspicuous in close proximity. Moreover, in a case in which the radius of the arc is larger than 20 mm, the width of swelling from each side 13 of the original shape 11 to the center side is small and the compressed area of the embossed portion 10 becomes large, so that the touch feeling may be deteriorated.
[0072] The embossed portion 10 is preferably formed such that at least a 1 mm diameter, and an inside of a circle having preferably a 1 mm to 10 mm diameter is squeezed from the center. In other words, as depicted in
[0073] A planar arrangement pattern of the plurality of embossed portions 10, 10, . . . may be any pattern, and as depicted in
[0074] As depicted in
[0075] As depicted in
[0076] Moreover, by making the size C of the embossed portion 10 larger than the interval B between the embossed portions 10, 10, it becomes difficult for the liquid permeable top sheet 3 to bend from a part of the embossed portion 10 on each outline 14 as a base point, and the effect of forming the outline 14 by a curve is able to be promoted.
[0077] As a modified example of the arrangement pattern of the embossed portions 10, as depicted in
[0078] As depicted in
DESCRIPTION OF THE REFERENCE NUMERAL
[0079] 1 sanitary napkin, 2 liquid impermeable back sheet, 3 liquid permeable top sheet, 4 absorbent body, 5 wrapping sheet, 6 second sheet, 7 side sheet, 10 embossed portion, 11 original shape, 12 corner, 13 side, 14 outline, 15 liquid intensive region, and 16 influence line