JP6883388B2 - Absorbent article - Google Patents

Description

The present invention relates to absorbent articles such as disposable diapers, urine pads (including incontinence pads), sanitary napkins and the like.

Conventionally, various absorbent articles with elaborate shapes of absorbers and absorbent cores (absorbent cores) have been known. For example, Patent Document 1 describes an absorption pad including a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber interposed between them, and the absorber has mountain folds and valley folds. It has a bellows structure formed repeatedly, and the ridges and ridges formed by each mountain fold and valley fold of the absorber extend in the anteroposterior direction connecting the front side and the back side of the wearer's body. The existing absorbent pads are disclosed. Patent Document 2 describes an absorbent article having an absorbing core between a top sheet and a back sheet, and includes an abdominal panel, a crotch panel, a back panel, and an outer edge panel in which the absorbing core can bend between the panels. Disclosed are absorbent articles that are broadly classified at intervals, and each major panel is independently configured to be bendable back and forth and left and right within each panel surface. Patent Document 3 describes an absorbent article having a vertically long absorbent body including a front surface sheet, a back surface sheet, and an absorbent body interposed between both sheets, and the absorbent body is on the upper surface side thereof in the width direction. Disclosed is an absorbent article in which a plurality of lateral grooves extending in the longitudinal direction are provided at a predetermined pitch in the longitudinal direction.

Japanese Unexamined Patent Publication No. 2014-83277 Japanese Unexamined Patent Publication No. 2004-49507 Japanese Unexamined Patent Publication No. 2007-14635

The absorbent articles disclosed in Patent Documents 1 to 3 have been devised in the three-dimensional shape of the absorbent body and the absorbent core in order to improve the fit in the crotch portion of the wearer and the absorbent capacity. However, absorbent articles are required to have such a feeling of wearing and absorption ability. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an absorbent article having an excellent wearing feeling and a ensured absorbency.

The absorbent article of the present invention that could solve the above-mentioned problems is an absorbent article having a width direction and a front-rear direction, and having an absorbent core provided between a top sheet and a back sheet. The absorbent core contains at least pulp fibers and, together with the topsheet, is formed in a bellows shape with alternating peaks and valleys in the anterior-posterior direction; the topsheet has one side and the other side in the width direction. It is characterized in that it is tilted outward in the width direction and has a central flap that overlaps with at least a part of the bellows-shaped absorbent core.

In the absorbent article of the present invention, since the absorbent core is formed in a bellows shape having alternating peaks and valleys in the front-rear direction together with the top sheet, it is easy to form a curve in the front-rear direction, and the crotch portion of the wearer. In addition to being able to improve the fit in the crotch area, the presence of the peaks and valleys enhances the cushioning property in the crotch area, which can improve the wearing feeling. Further, due to the bellows-shaped valley portion, a gap extending in the width direction is likely to be formed between the top sheet and the wearer's skin, and the air permeability can be improved. Then, an absorbent article is provided on one side and the other side in the width direction of the top sheet by providing a central flap that is tilted outward in the width direction and overlaps with at least a part of the absorbent core formed in a bellows shape. Diffusibility of urine and the like in the anterior-posterior direction is ensured on the skin surface side of the skin, and the absorbent core can exert an absorptive capacity in a wide range in the anterior-posterior direction.

It is preferable that the length L1 in the anteroposterior direction in the bellows-shaped state of the absorbent core is 0.5 times or more and 0.9 times or less the length L2 in the anterior-posterior direction in the state where the bellows is spread. If the absorbent core is formed in a bellows shape so that the ratio of L1 / L2 is in such a range, the absorbent core is formed in a bellows state with an appropriate thickness, and cushioning property and breathability are suitably ensured. At the same time, the absorbent core becomes excessively less bulky.

The central flap is preferably provided so that the distance between the upright base of the central flap on one side and the upright base of the central flap on the other side is 60 mm or less. By providing the central flap in this way, it becomes easy for the central flap to cover a wide range of the absorbent core formed in a bellows shape.

The central flap is preferably provided with an elastic member extending in the front-rear direction. By providing an elastic member on the central flap, the contraction force of the elastic member causes the central flap to rise toward the wearer's skin, making it easier for a space to be formed between the wearer's skin and the top sheet, ensuring breathability. It will be easier. In addition, the central flap facilitates the formation of a diffusion path for urine and the like to diffuse in the anteroposterior direction.

It is preferable that the central flap is provided with a plurality of elastic members extending in the front-rear direction arranged side by side in the width direction. By providing the elastic member on the central flap in this way, the rigidity of the central flap can be increased as a whole, a space is easily formed between the wearer's skin and the top sheet, and the central flap is formed in a bellows shape. The unevenness of the absorbent core is less likely to be transmitted to the wearer's skin.

The central flap is preferably made of a liquid permeable non-woven fabric. By constructing the central flap in this way, urine or the like can permeate through the central flap and be suitably absorbed by the absorbent core. In addition, the central flap can be softened to the touch to improve the wearing feeling.

The absorbent core preferably has an opening or recess extending in the anteroposterior direction between the central flap on one side and the central flap on the other side. By forming the opening or the recess in the absorbent core in this way, the air permeability in the opening or the recess is enhanced. Further, the opening or the recess functions as a diffusion path in the anteroposterior direction of urine or the like, and the absorbent core easily contributes to the absorption of urine or the like over a wide range.

It is preferable that a leak-proof flap tilted inward in the width direction is provided on the outer side of the central flap in the width direction. The leak-proof flap prevents lateral leakage of urine and the like. At this time, the distance between the central flap and the leak-proof flap is such that the distance between the standing base of the central flap and the standing base of the leak-proof flap is between the standing base of the central flap on one side and the standing base of the central flap on the other side. It is preferably provided so as to be longer than the distance of the above, which allows a wider range of the absorbent core formed in a bellows shape by the central flap. Further, since the leakage-proof flap is provided on the outer side in the width direction of the absorbent article, the absorbent core can contribute to the absorption of urine or the like in a wider range in the width direction.

In the absorbent article of the present invention, since the absorbent core is formed in a bellows shape having alternating peaks and valleys in the front-rear direction together with the top sheet, it is easy to form a curve in the front-rear direction, and the crotch portion of the wearer. In addition to being able to improve the fit in the crotch area, the presence of the peaks and valleys enhances the cushioning property in the crotch area, which can improve the wearing feeling. Further, due to the bellows-shaped valley portion, a gap extending in the width direction is likely to be formed between the top sheet and the wearer's skin, and the air permeability can be improved. Then, an absorbent article is provided on one side and the other side in the width direction of the top sheet by providing a central flap that is tilted outward in the width direction and overlaps with at least a part of the absorbent core formed in a bellows shape. The diffusivity of urine and the like in the anterior-posterior direction on the skin surface side is ensured, and the absorbent core can exert an absorptive capacity in a wide range in the anteroposterior direction.

An example of the absorbent article of the present invention is shown, and a plan view of the absorbent article as viewed from the skin surface side is shown. FIG. 1 shows a cross-sectional view taken along the line II-II of the absorbent article shown in FIG. FIG. 1 shows a cross-sectional view taken along line III-III of the absorbent article shown in FIG. Another example of the absorbent article of the present invention is represented, and the plan view of the absorbent article viewed from the skin surface side is shown. FIG. 4 shows a VV cross-sectional view of the absorbent article shown in FIG.

The absorbent article of the present invention has a top sheet, a back sheet, and an absorbent core provided between them, and has a width direction and a front-rear direction. Examples of the absorbent article of the present invention include disposable diapers, urine pads (including incontinence pads), sanitary products and the like.

In the present invention, the anteroposterior direction of the absorbent article means a direction extending in the anteroposterior direction of the wearer's crotch when the absorbent article is worn by the wearer. The width direction of the absorbent article means a direction that is on the same plane as the absorbent article and is orthogonal to the front-rear direction. Further, the skin surface side of the absorbent article means the side facing the skin of the wearer when the absorbent article is worn, and the outer surface side of the absorbent article is the wearer when the absorbent article is worn. Means the opposite side.

The shape of the absorbent article is not particularly limited. When the absorbent article is a urine pad, the shape of the absorbent article is shown to be substantially rectangular, hourglass-shaped, gourd-shaped or the like.

When the absorbent article is a disposable diaper, the absorbent article is composed, for example, of an anterior and posterior portions and a crotch located between them and provided with an absorbent core. As a disposable diaper, for example, an absorbent body in which an absorbent core is arranged between a top sheet and a back sheet on the skin side surface of an exterior member consisting of a front side portion, a rear side portion, and a crotch portion located between them. May be provided. At this time, a substantially rectangular shape or the like is shown as the shape of the absorbent body. As a disposable diaper, a laminate in which an absorbent core is arranged between the top sheet and the back sheet may form a front side portion, a rear side portion, and a crotch portion located between them. The front side portion corresponds to a portion to be applied to the ventral side of the wearer when wearing a disposable diaper, and the posterior side portion corresponds to a portion to be applied to the back side of the wearer when wearing a disposable diaper. The crotch portion is located between the anterior side portion and the posterior side portion, and corresponds to a portion that is applied to the wearer's crotch.

When the absorbent article is a disposable diaper, the disposable diaper is an open type (tape type) disposable diaper in which fastening members are provided at the left and right ends of the rear side portion, and the fastening members form a pants shape when worn. Or it may be a pants-type disposable diaper in which a waist opening and a pair of leg openings are formed.

The top sheet is a sheet provided on the skin surface side of the absorbent core, and is preferably liquid permeable. Examples of the top sheet include non-woven fabrics formed from hydrophilic fibers such as cellulose, rayon and cotton, and hydrophobicity such as polyolefins (eg polypropylene, polyethylene), polyesters (eg PET) and polyamides (eg nylon). A non-woven fabric formed from fibers, in which the surface of the hydrophobic fibers is hydrophilized by a surfactant, or the like can be used. Further, as the top sheet, a woven fabric, a knitted fabric, a perforated plastic film or the like may be used.

The back sheet is a sheet provided on the outer surface side of the absorbent core, and is preferably liquid-impermeable. As the back sheet, a non-woven fabric formed of hydrophobic fibers such as polyolefin (for example, polypropylene, polyethylene), polyester (for example, PET), and polyamide (for example, nylon), a plastic film, or the like can be used. Further, a laminate of a non-woven fabric and a plastic film may be used. In the present invention, the liquid impermeable also includes the meaning of water repellency.

The exterior member may be liquid-permeable or liquid-impermeable, and a sheet material that can be used for the top sheet or back sheet can be used. The exterior member is preferably formed by laminating an outer sheet on an inner sheet, and more preferably formed by laminating a liquid-impermeable outer sheet on a hydrophilic inner sheet.

When a non-woven fabric is used as each of the sheet materials described above, it is preferable to use a spunbonded non-woven fabric, an air-through non-woven fabric, a point-bonded non-woven fabric, a melt-blown non-woven fabric, an air-laid non-woven fabric, an SMS non-woven fabric, or the like.

The absorbent core is not particularly limited as long as it contains an absorbent material capable of absorbing excrement such as urine. As the absorbent core, for example, a molded body obtained by molding an absorbent material into a predetermined shape can be used. The absorbent core may be covered with a sheet member such as a paper sheet (eg, tissue paper or tissue paper) or a liquid permeable non-woven fabric. Examples of the absorbent material contained in the absorbent core include hydrophilic fibers such as pulp fibers and water-absorbent resins such as polyacrylic acid-based, polyaspartic acid-based, cellulosic-based, and starch / acrylonitrile-based. Further, the absorbent material includes heat-sealing fibers such as polyolefin fibers (for example, polyethylene fibers, polypropylene fibers, etc.), polyester fibers (for example, PET fibers), polyamide fibers (for example, nylon fibers), and the like. May be good. These heat-sealing fibers may be hydrophilized with a surfactant or the like in order to enhance the affinity with urine or the like.

In the absorbent article of the present invention, the absorbent core contains at least pulp fibers as the absorbent material. The pulp fibers are preferably contained in the absorbent core as an aggregate of spread pulp fibers. If the absorbent core contains pulp fibers, the shape-retaining property of the absorbent core is enhanced, and as will be described later, the absorbent core is easily formed in a bellows shape, and the absorbent core formed in a bellows shape is easily formed. Cushioning can be improved. In addition, it becomes easier to quickly absorb urine and the like excreted from the wearer. The absorbent core preferably contains a water-absorbent resin from the viewpoint of further increasing the absorption capacity. In this case, for example, an aggregate of pulp fibers mixed or sprayed with a water-absorbent resin can be used. The absorbent core preferably contains, for example, pulp fiber in an amount of 50% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass or more. The ratio represents the content of pulp fibers in 100% by mass of the absorbent core.

Basis weight of the absorbent core, for example, 100 g / m ² or more preferably, 120 g / m ² or more, and more preferably 135 g / m ² or more, preferably 400 g / m ² or less, 350 g / m ² or less More preferably, 300 g / m ² or less is further preferable, and 250 g / m ² or less is particularly preferable. In the absorbent article of the present invention, the absorbent core is formed in a bellows shape as described later, but the basis weight of the absorbent core described here is the basis weight in which the bellows of the absorbent core is expanded. means.

The shape (planar shape) of the absorbent core is not particularly limited. The shape of the absorbent core may be appropriately determined according to the intended use, and examples thereof include a substantially rectangular shape, an hourglass shape, a gourd shape, and a battledore shape.

The absorbent core may be formed by laminating a plurality of layers. For example, the absorbent core may have an upper absorbing layer provided on the top sheet side and a lower absorbing layer provided on the back seat side. The upper absorbing layer and the lower absorbing layer are not particularly limited as long as they contain an absorbent material, and their shapes (planar shapes) are not particularly limited, as in the above description of the absorbent core.

In the absorbent article of the present invention, the absorbent core, together with the top sheet, is formed in a bellows shape having alternating peaks and valleys in the front-rear direction. By constructing the absorbent article of the present invention in this way, it becomes easy to form a curve in the front-rear direction, the fit in the crotch portion of the wearer can be improved, and the crotch portion is present due to the presence of the peak portion and the valley portion. The cushioning property at the part is enhanced, and the wearing feeling when the absorbent article is attached can be improved. Further, even when the absorbent article is attached so as to be in close contact with the wearer's skin, a gap extending in the width direction is likely to be formed between the top sheet and the wearer's skin due to the bellows-shaped valley portion. , It becomes easier to secure breathability. Therefore, it is possible to reduce stuffiness when wearing an absorbent article.

The bellows-shaped absorbent core and the top sheet described above can be formed by bending the absorbent core in a bellows shape in the front-rear direction of the absorbent article in a state where the absorbent core is overlapped with the top sheet. Therefore, the absorbent core overlaps the topsheet in both the peaks and valleys of the bellows. The ridges and valleys formed by bending the absorbent core together with the top sheet in a bellows shape correspond to the ridges seen from the top sheet side and the valleys seen from the back sheet side of the absorbent core. The valley seen from the seat side corresponds to the mountain part seen from the back seat side of the absorbent core. In the present invention, unless otherwise specified, the peaks and valleys of the bellows are defined when viewed from the skin surface side (top sheet side) of the absorbent article.

The ridges and valleys of the bellows may be formed so that the ridges and valleys alternately exist in the front-rear direction in the anteroposterior cross section of the absorbent article (that is, the cross section in the cutting line extending in the anteroposterior direction). The peaks and valleys of the bellows are formed so as to extend substantially in the width direction of the absorbent article, but do not have to extend completely in the width direction and extend diagonally with respect to the width direction. It may be present or may extend in a curved shape. Further, two (or more) peaks may be merged in the middle of extending in the substantially width direction to form one peak, and two (or more) valleys may extend in the substantially width direction. It may be merged on the way to form one valley. The length of the front-back method of each peak (or the length of each valley in the front-back direction) may be the same or different. The absorbent core and the top sheet need only be bent in a bellows shape in the front-rear direction as a whole.

When the absorbent core is divided into three equal parts in the front-rear direction to form an intermediate portion between the front portion and the rear portion, it is preferable that at least the intermediate portion is formed in a bellows shape. More preferably, the middle portion is formed in a bellows shape over the entire anterior-posterior direction. The absorptive core may also be formed in a bellows shape at the anterior and posterior parts. The middle portion of the absorbent core is defined by being divided into three equal parts in the front-rear direction in a state where the absorbent core is formed in a bellows shape, for example, in a state of no load such as placing it on a horizontal table.

It is preferable that a plurality of peaks and valleys of each of the bellows-shaped absorbent cores are provided. The number of peaks and valleys formed in the absorbent core is preferably 5 or more, preferably 8 or more, and even more preferably 10 or more. The upper limit of the number of peaks and valleys formed in the absorbent core is not particularly limited, but may be, for example, 50 or less, 40 or less, or 30 or less. .. The number of peaks and valleys formed in the absorbent core shall be counted in the anteroposterior cross section of the absorbent core. Further, the number of peaks and valleys formed in the middle portion of the absorbent core is preferably 3 or more, preferably 5 or more, and even more preferably 7 or more. The upper limit of the number of peaks and valleys formed in the middle portion of the absorbent core may be, for example, 30 or less, or 25 or less.

It is preferable that the length L1 in the anteroposterior direction in the bellows-shaped state of the absorbent core is 0.5 times or more and 0.9 times or less the length L2 in the anterior-posterior direction in the state where the bellows is spread. If the absorbent core is formed in a bellows shape so that the ratio of L1 / L2 is in such a range, the absorbent core is formed in a bellows state with an appropriate thickness, and cushioning property and breathability are suitably ensured. At the same time, the absorbent core becomes excessively less bulky. The ratio of L1 / L2 is more preferably 0.6 times or more, and more preferably 0.8 times or less.

The absorbent core is preferably directly or indirectly adhered to the topsheet, at least throughout the anterior-posterior intermediate portion, and directly or indirectly adhered to the topsheet over the entire absorbent core. Is more preferable. For example, when the absorbent core is divided into a mesh of 1 cm in the front-rear direction and the width direction in the expanded state (the bellows are expanded), the intermediate portion of the absorbent core or the entire absorbent core is divided. It is preferable that the absorbent core is directly or indirectly adhered to the topsheet in any region. By adhering the absorbent core and the top sheet in this way, the absorbent core is likely to be formed in a bellows shape together with the top sheet.

It is preferable that the absorbent core and the top sheet are adhered by an adhesive applied in a predetermined pattern such as a net shape, a linear shape, or a scattered spot shape. The absorbent core and the top sheet are preferably bonded in a linear adhesive pattern, which makes it easier to improve the liquid permeability of the top sheet. The linear adhesive pattern may be linear, curved, or a combination thereof. Examples of the curved adhesive pattern include a pattern in which the adhesive is applied in a meandering shape or a spiral shape (spiral shape). The meandering shape includes, for example, a sinusoidal shape, an Ω-shaped repeating pattern, and the like. The linear adhesive pattern can be formed by applying an adhesive by a coater method, a bead method, an omega coating method, a spiral coating method, a pattern coating or the like.

As the adhesive, it is convenient in manufacturing to use a hot melt adhesive, and it is particularly preferable to use a rubber-based hot melt adhesive. The rubber-based hot melt adhesive preferably contains a styrene-based elastomer, and the styrene-based elastomer includes a styrene-isoprene-styrene block copolymer (SIS) and a styrene-butadiene-styrene block copolymer (SBS). , Styrene-ethylene-butadiene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS) and the like. As the above-exemplified styrene-based elastomer, only one type may be used, or two or more types may be used in combination.

The absorbent core may be formed in a bellows shape together with the back sheet in addition to the top sheet. In this case, the absorbent core is preferably adhered directly or indirectly to the backsheet. Adhesion between the absorbent core and the back sheet may be performed according to the adhesion between the absorbent core and the top sheet described above.

The bellows of the absorbent core may be bonded to adjacent peaks or valleys, or may be formed to be expandable in the anteroposterior direction. In the latter case, an elastic member extending in the front-rear direction may be provided on the absorbent core, the top sheet, or the back sheet.

The absorbent core is preferably bent in a bellows shape in the entire thickness direction, and the absorbent core is made of an absorbent material because it is easy to form the absorbent core in this way. It is preferable to have only one absorbent layer made of an absorbent material rather than having a plurality of layers. Specifically, the absorbent core preferably has only one absorbent layer containing at least pulp fibers.

By the way, as described above, when the absorbent core is formed in a bellows shape having peaks and valleys alternately in the anteroposterior direction together with the top sheet, the diffusivity of urine or the like in the anteroposterior direction is reduced on the top sheet. However, there is a risk that the absorptive capacity at the front and rear of the absorptive core will not be fully utilized. Therefore, in the absorbent article of the present invention, the central flap is tilted outward in the width direction on one side and the other side in the width direction of the top sheet and overlaps with at least a part of the absorbent core formed in a bellows shape. It is provided. The central flap is provided on the skin side of the top sheet. By providing the central flap in this way, the diffusivity of urine and the like in the anterior-posterior direction is ensured on the skin surface side of the absorbent article, and the absorbent core can exert its absorbency in a wide range in the anterior-posterior direction. Become.

The central flap may be provided so as to overlap at least a portion of the bellows-shaped portion of the absorbent core. The overlap between the central flap and the absorbent core is defined with the central flap lying outward in the width direction. The central flap is preferably provided so as to overlap at least the middle portion in the front-rear direction of the absorbent core, and may be further provided so as to overlap the front portion and the rear portion of the absorbent core. The central flap may be provided over the entire anteroposterior direction of the absorbent core. It is preferable that the central flap is not provided so as to overlap over the entire width direction of the absorbent core. Specifically, the absorbent core preferably extends outward from the widthwise outer edge of the central flap, with the central flap lying outward in the width direction, thereby providing an absorbent article. It becomes easier to secure the breathability when wearing. More preferably, the absorptive core extends outward from the lateral outer edge of the central flap at all of the anterior, intermediate and posterior portions.

The central flaps are provided on one side and the other side in the width direction of the top sheet, respectively, but it is preferable that the central flap on one side and the central flap on the other side are provided close to each other. Specifically, the distance between the upright base of the central flap on one side and the upright base of the central flap on the other side (that is, the distance between the upright bases of the central flap) is preferably 60 mm or less, preferably 50 mm or less. It is more preferably present, and more preferably 40 mm or less. By providing the central flap in this way, it becomes easy for the central flap to cover a wide range of the bellows-shaped portion of the absorbent core (particularly, the portion including the central portion in the width direction of the absorbent core). The starting point at which the central flap rises is referred to as the standing base, and the rising tip of the central flap is referred to as the free end.

The distance between the standing bases of the central flap is preferably 1.8 times or less, more preferably 1.6 times or less, the length from the standing base of the central flap to the free end. By forming the central flap in this way, the central flap is less likely to fall inward in the width direction. That is, even if the central flap on one side is about to fall inward in the width direction, the central flap on the other side is likely to be an obstacle to prevent the central flap from completely falling inward in the width direction. Become.

The central flap is preferably provided with an elastic member extending in the front-rear direction. By providing an elastic member on the central flap, the contraction force of the elastic member causes the central flap to rise toward the wearer's skin, making it easier for a space to be formed between the wearer's skin and the top sheet, ensuring breathability. It will be easier. In addition, the central flap facilitates the formation of a diffusion path for urine and the like to diffuse in the anteroposterior direction.

The central flap is preferably provided with an elastic member at least in the vicinity of the free end. Specifically, when the region from the standing base of the central flap to the free end is divided into three equal parts to form the base side region, the free end side region, and the intermediate region between them, an elastic member is provided at least in the free end side region. Is preferable. The elastic member provided in the free end side region allows the free end of the central flap to be raised high, which facilitates the formation of a wider space between the wearer's skin and the top seat.

It is preferable that the central flap is provided with a plurality of elastic members extending in the front-rear direction arranged side by side in the width direction. By providing the elastic member on the central flap in this way, the rigidity of the central flap can be increased as a whole, a space is easily formed between the wearer's skin and the top sheet, and the central flap is formed in a bellows shape. The unevenness of the absorbent core can be less likely to be transmitted to the wearer's skin. More preferably, the central flap is provided with elastic members in the base side region and / or the intermediate region in addition to the free end side region.

The elastic member may be fixed to the central flap by a known joining means such as an adhesive. When a plurality of elastic members are provided side by side in the width direction on the central flap, it is preferable to provide a region in which the adhesive is not applied (adhesive non-applied region) between the adjacent elastic members. The central flap is less likely to be formed by being stretched by the adhesive, and the feel of the central flap can be improved.

It is preferable that the front and rear ends of the outer surface in the width direction of the central flap are directly or indirectly joined to the top sheet in order to tilt outward in the width direction and facilitate standing up. By joining the front and rear ends of the outer surface of the central flap in the width direction to the top sheet, a portion between the front end and the rear end of the central flap is formed so as to be able to stand upright. The outer surface of the central flap means the outer surface of the central flap with respect to the width direction in the state where the central flap is raised. The front end and the rear end of the central flap are defined as the portion including the front end or the rear end of the center flap, respectively, and the front end is 0% and the rear end is 100 as the relative position of the center flap with respect to the front-rear direction. When% is set, for example, the front end portion corresponds to a region of 0% to 15%, and the rear end portion corresponds to a region of 85% to 100%. The relative position is defined in a state where the absorbent article is completely spread out, and when an elastic member is provided on the central flap, the relative position is defined in a state where the elastic member is cut into small pieces and no contraction force is exhibited.

The central flap can be formed, for example, by arranging the center sheet on the top sheet and joining the central portion in the width direction of the center sheet to the top sheet. Alternatively, it can be formed by arranging the right center sheet and the left center sheet on both sides in the width direction of the top sheet, and joining the inner portions of the right center sheet and the left center sheet in the width direction to the top sheet. When the elastic members are provided on the central flaps, the elastic members may be attached to these center sheets.

The central flap may be liquid permeable or liquid impermeable, so the center sheet (including the left and right center sheets) is a sheet material that can be used for top and back sheets. Can be used. The central flap or center sheet is preferably liquid permeable, whereby urine or the like can permeate the central flap or center sheet and be suitably absorbed by the absorbent core. More preferably, the central flap or center sheet is made of a liquid-permeable non-woven fabric, which can soften the feel of the central flap and improve the wearing feeling.

The absorbent core preferably has an opening or recess extending in the front-rear direction at the center in the width direction. The opening or recess may include a center line in the width direction of the absorbent core and may be formed so as to extend in the front-rear direction along the center line. The opening or recess extending in the front-rear direction means an opening or recess having a shape longer in the front-rear direction than in the width direction. By forming the opening or the recess in the absorbent core in this way, the air permeability in the opening or the recess is enhanced. Further, the opening or the recess functions as a diffusion path in the anteroposterior direction of urine or the like, so that the urine or the like is quickly absorbed by the absorbent article, and the absorbent core easily contributes to the absorption of the urine or the like over a wide range.

The opening is provided through the absorbent core in the thickness direction. The recesses are formed by partially reducing the basis weight of the absorbent core. The concave portion is preferably formed so that the basis weight is 60% by mass or less (more preferably 50% by mass or less, still more preferably 40% by mass or less) than the portion other than the concave portion.

When the recesses are formed in the absorbent core, the recesses may be formed on the surface of the absorbent core on the top sheet side or on the surface of the back seat side. When the absorbent core is composed of an upper absorbing layer and a lower absorbing layer, an opening is formed in the upper absorbing layer, and the lower absorbing layer is provided so as to cover the opening, so that the absorbing core has a recess. On the contrary, an opening may be formed in the lower absorption layer, and a recess may be formed in the absorbent core by providing the upper absorption layer so as to cover the opening. Preferably, the recess is formed on the topsheet side surface of the absorbent core.

The absorbent core may be provided with only one opening or recess, or may be provided with two or more openings or recesses, but preferably only one opening or recess is provided in the absorbent core. That is, it is preferable that the absorbent core is provided with only one opening or recess, and the opening or recess is provided at the center in the width direction so as to extend in the front-rear direction. By forming an opening or a recess in the absorbent core in this way, the absorbent core is formed in a bellows shape in the portion where the wearer's buttocks are placed to ensure cushioning, and between the left and right buttocks. Can be provided with openings or recesses to enhance breathability.

The width direction of the opening or recess is preferably 5% or more, more preferably 8% or more, still more preferably 10% or more of the width direction of the narrowest portion of the absorbent core. Further, 30% or less is preferable, 25% or less is more preferable, and 20% or less is further preferable. The narrowest portion of the absorbent core means the narrowest portion formed in the width direction in the middle portion in the front-rear direction of the absorbent core. The width of the opening or recess is also preferably 5 mm or more, more preferably 8 mm or more, preferably 35 mm or less, and more preferably 25 mm or less.

The opening or recess is preferably provided at least in the anterior-posterior intermediate portion of the absorbent core and may extend further to the anterior and / or posterior portion of the absorbent core. It should be noted that the openings or recesses are preferably not provided over the entire anterior-posterior direction of the absorbent core, that is, the anterior end of the opening or recess is located posterior to the anterior end of the absorbent core and is posterior to the opening or recess. The ends are preferably located anterior to the posterior ends of the absorbent core.

Of the openings and recesses, the absorbent core is preferably provided with an opening. If an opening extending in the front-rear direction is provided in the center of the absorbent core in the width direction, the bellows of the absorbent core will not be distorted even if an inward force in the width direction is applied to the absorbent core. , The absorbent core is likely to be suitably maintained in a bellows shape.

The absorbent article is preferably provided with a leak-proof flap that is tilted inward in the width direction on the outside in the width direction of the central flap. The leak-proof flap prevents lateral leakage of urine and the like.

The leak-proof flap is preferably provided with an elastic member extending in the front-rear direction. By providing the elastic member on the leak-proof flap, the leak-proof flap can easily stand up toward the wearer's skin due to the contraction force of the elastic member. It is preferable that the leakage-proof flap is provided with an elastic member at least in the vicinity of the free end when the rising starting point is the standing base and the rising tip is the free end. Specifically, when the region from the standing base of the leak-proof flap to the free end is divided into three equal parts to form the base side region, the free end side region, and the intermediate region between them, the elastic member is at least in the free end side region. It is preferable to be provided. The leak-proof flap may be provided with a plurality of elastic members arranged side by side in the width direction.

The elastic member may be fixed to the leak-proof flap by a known joining means such as an adhesive. When a plurality of elastic members are provided side by side in the width direction on the leak-proof flap, it is preferable to provide a region (adhesive non-coated region) between adjacent elastic members in which no adhesive is applied. As a result, the leak-proof flap is less likely to be formed by being stretched by the adhesive, and the feel of the leak-proof flap can be improved.

The leak-proof flap may be provided over the entire length of the absorbent article in the anteroposterior direction, or may be provided in a part of the absorbent article in the anteroposterior direction. From the viewpoint of enhancing the lateral leakage prevention effect of the leakage-proof flap, the leakage-proof flap is preferably provided with a length of 70% or more in the front-rear direction of the absorbent article, more preferably 80% or more, and 90% or more. Is even more preferable.

The leak-proof flap is preferably directly or indirectly joined to the top sheet at the front and rear ends of the inner side surface in the width direction in order to tilt inward in the width direction and facilitate standing up. By joining the front and rear ends of the inner side surface of the leak-proof flap in the width direction to the top sheet, a portion between the front end and the rear end of the leak-proof flap is formed so as to be able to stand upright. The inner surface of the leak-proof flap means the inner surface of the leak-proof flap in the width direction with the leak-proof flap standing up. The front end and the rear end of the leak-proof flap are defined as the portion including the front end or the rear end of the leak-proof flap, respectively, and the front end is set to 0% as the relative position of the leak-proof flap in the front-rear direction. When the end is 100%, for example, the front end corresponds to a region of 0% to 15%, and the rear end corresponds to a region of 85% to 100%. The relative position is defined in a state where the absorbent article is completely spread out, and when an elastic member is provided on the leak-proof flap, the relative position is defined in a state where the elastic member is cut into small pieces and no contraction force is generated. ..

The leak-proof flap is preferably provided so as not to overlap the central flap. Specifically, it is preferable that the central flap and the leak-proof flap are formed so as to be separated from each other in a prone state. When the central flap and the leak-proof flap are formed in this way, when the absorbent article is used, the central flap and the leak-proof flap can easily stand up without being disturbed by each other.

For the central flap and the leak-proof flap, the distance between the standing base of the central flap and the standing base of the leak-proof flap is greater than the distance between the standing base of the central flap on one side and the standing base of the central flap on the other side. It is preferable that it is provided so as to be long. In this case, since the central flaps on one side and the other side in the width direction are provided close to each other, the absorbent core formed in a bellows shape by the central flaps can be covered over a wider area. Further, since the leak-proof flap is provided on the outer side in the width direction of the absorbent article, a wide range of the absorbent core can contribute to the absorption of urine and the like, and the leak-proof flap causes lateral leakage of urine and the like. It will be effectively prevented. The distance between the erecting base of the central flap and the erecting base of the leak-proof flap means the distance between the central flap and the leak-proof flap located on the outer side in the width direction of the central flap.

The leak-proof flap can be formed, for example, by joining side sheets extending in the front-rear direction to both sides of the top sheet in the width direction and providing elastic members in the inner portion of the side sheet in the width direction. By providing the side sheet and the elastic member in this way, the inner portion of the side sheet in the width direction rises toward the wearer's skin due to the contraction force of the elastic member, and a leak-proof flap is formed. The leak-proof flap or side sheet is preferably made of a liquid-impermeable plastic film, a liquid-impermeable non-woven fabric, or the like.

In addition to the elastic member described above, the absorbent article of the present invention may be further provided with another elastic member. For example, the absorbent article may be provided with elastic members extending in the front-rear direction at both ends in the width direction, or may be provided with elastic members extending in the width direction at both ends in the front-rear direction. By providing elastic members extending in the front-rear direction at both ends in the width direction of the absorbent article, the fit around the legs of the wearer is enhanced, and leakage of urine or the like from around the legs is prevented. By providing elastic members extending in the width direction at both ends of the absorbent article in the front-rear direction, the fit around the waist of the wearer is enhanced, and leakage of urine or the like from the abdomen or back is prevented.

In addition, an elastic member extending in the front-rear direction may be provided between the central flap on one side and the central flap on the other side, whereby the standing base of the central flap is lifted toward the wearer's skin, and the absorbent article. When worn, the central flap overlaps with the bellows-shaped absorbent core for easy positioning.

As each of the elastic members described above, elastic elastic materials used for ordinary absorbent articles such as polyurethane threads, polyurethane films, and natural rubber can be used. The elastic member is preferably fixed with an adhesive such as a hot melt adhesive in a stretched state. For example, a polyurethane yarn having a fineness of 40 to 1,240 dtex is stretched to a magnification of 1.1 to 5.0 times, arranged, and fixed. As the joining means, a rubber-based hot melt adhesive is preferably used. The magnification is 1.0 times in the non-stretched state.

Next, a configuration example of the absorbent article of the present invention will be described with reference to the drawings. In the drawing, an open type (tape type) disposable diaper is shown as an absorbent article. The present invention is not limited to the embodiments shown in the drawings.

1 to 3 show an example of the absorbent article of the present invention. FIG. 1 shows a plan view of an open-type disposable diaper as an absorbent article as viewed from the skin surface side, FIG. 2 shows a sectional view taken along line II-II of the absorbent article shown in FIG. A III-III partial cross-sectional view of the absorbent article shown in FIG. 1 is shown. The cross-sectional view III-III of FIG. 3 shows a cross-sectional view of a portion where the absorbent core is folded in a bellows shape. In the figure of the present application, the arrow x represents the width direction, the arrow y represents the front-back direction, and the direction perpendicular to the surface formed by the arrows x and y represents the thickness direction (vertical direction) z. In FIG. 1, the upper side of the drawing corresponds to the front side of the absorbent article, and the lower side of the drawing corresponds to the rear side of the absorbent article.

The absorbent article 1 (1A) has an absorbent core 4 arranged between the top sheet 2 and the back sheet 3. The excrement that has penetrated the top sheet 2 is contained by the absorbent core 4. The back sheet 3 is provided on the outer surface side of the absorbent core 4 to prevent excrement from leaking to the outside. In the absorbent article 1A, the absorbent core 4 is formed in an hourglass shape.

Fastening members 15 are attached to the left and right end portions of the absorbent article 1A at the rear side portion in the front-rear direction y. The fastening member 15 is configured by providing a fastener 17 on the base sheet 16. The absorbent article 1A can be attached by putting it in the crotch of the wearer and joining the fastener 17 of the fastening member 15 to the outer surface of the front side portion of the absorbent article 1A. As the fastener 17, a hook member of a hook, a loop, or a fastener or an adhesive can be adopted.

The absorbent core 4 contains at least pulp fibers and is formed in a bellows shape having mountain portions 5A and valley portions 5B alternately in the front-rear direction y together with the top sheet 2. By forming the absorbent core 4 together with the top sheet 2 in a bellows shape, a bellows portion 5 having a peak portion 5A and a valley portion 5B is formed. By forming the bellows portion 5 in this way, the absorbent article 1A can be easily formed to be curved in the front-rear direction y, the fit in the crotch portion of the wearer can be improved, and the cushioning property in the crotch portion can be improved. Can be enhanced. Further, due to the valley portion 5B of the bellows portion 5, a gap extending in the width direction x is likely to be formed between the top sheet 2 and the wearer's skin, and it is easy to secure breathability. As shown in FIG. 3, in the absorbent article 1A, the absorbent core 4 is bent in a bellows shape together with the top sheet 2 and the back sheet 3 to form the bellows portion 5.

The top sheet 2 is provided with a central flap 7 on one side and the other side in the width direction x, which is tilted outward in the width direction x and overlaps with at least a part of an absorbent core 4 formed in a bellows shape. ing. That is, the central flap 7 is provided so as to overlap with at least a part of the bellows portion 5. In the drawing, the center sheet 9 is arranged on the top sheet 2, and the central portion of the center sheet 9 in the width direction x is joined to the top sheet 2 so that both ends of the center sheet 9 in the width direction x stand up. As a result, the central flap 7 is formed. The central flap 7 is composed of a central flap 7A on one side in the width direction x and a central flap 7B on the other side. By providing the central flap 7, the diffusivity of excrement such as urine in the anteroposterior direction y is ensured on the skin surface side of the absorbent article 1A, and the absorbent core 4 easily contributes to the absorption of urine or the like over a wide range. Become. In the drawing, the central flap 7 is provided over the entire anteroposterior direction y of the absorbent core 4 and is inward of the outer edge of the absorbent core 4 in the width direction x over the entire anteroposterior direction y of the absorbent core 4. It is provided.

The central flap 7 is provided with an elastic member 8 extending in the front-rear direction y. By providing the elastic member 8 on the central flap 7, the central flap 7 stands up toward the wearer's skin, and it becomes easy to form a space between the wearer's skin and the top sheet 2, and it becomes easy to secure breathability. .. Further, a diffusion path for diffusing urine or the like in the anteroposterior direction y is likely to be preferably formed between the central flap 7A on one side and the central flap 7B on the other side.

In the absorbent article 1A, a plurality of elastic members 8 extending in the front-rear direction y are provided side by side in the width direction x on the central flap 7 (three on each of the central flap 7A on one side and the central flap 7B on the other side in the drawing). Has been done. By providing a plurality of elastic members 8 on the central flap 7, the rigidity of the central flap 7 can be increased as a whole, a space can be easily formed between the wearer's skin and the top sheet 2, and the bellows portion 5 It is possible to make it difficult for the unevenness of the surface to be transmitted to the wearer's skin.

The absorbent core 4 is formed with an opening 6 extending in the front-rear direction y between the central flap 7A on one side and the central flap 7B on the other side. By providing the opening 6 in the absorbent core 4, the air permeability in the opening 6 can be enhanced. Further, the opening 6 can also function as a diffusion path in the anteroposterior direction y of urine or the like.

Elastic members 13 for legs are provided on both sides of the absorbent article 1A in the width direction x on the outer side of the absorbent core 4 in the width direction x. The leg elastic member 13 forms leg gathers along the wearer's leg circumference to prevent leakage of excrement such as urine from the leg circumference.

At the end of the absorbent article 1A in the front-rear direction y, a waist elastic member 14 is provided outside the absorbent core 4 in the front-rear direction y. The elastic member 14 for the waist forms waist gathers along the waist circumference of the wearer, and prevents leakage of urine or the like from the back side or the ventral side.

Next, another configuration example of the absorbent article of the present invention will be described. FIG. 4 shows a plan view of an open-type disposable diaper as an absorbent article as viewed from the skin surface side, and FIG. 5 shows a VV cross-sectional view of the absorbent article shown in FIG. In the following description, the description of the part that overlaps with the above description will be omitted.

In the absorbent article 1 (1B) shown in FIGS. 4 and 5, a leak-proof flap 10 tilted inward in the width direction x is provided outside the width direction x of the central flap 7. The leak-proof flap 10 can prevent lateral leakage from the absorbent article 1B.

The leak-proof flap 10 is provided with an elastic member 11 extending in the front-rear direction y. By providing the elastic member 11 on the leak-proof flap 10, the leak-proof flap 10 can easily stand up toward the wearer's skin, and lateral leakage from the absorbent article 1B can be prevented.

In the drawing, the side sheet 12 is arranged on the top sheet 2, the outer portion of the side sheet 12 in the width direction x is joined to the top sheet 2 or the back sheet 3, and the inner portion of the side sheet 12 in the width direction x. The leak-proof flap 10 is formed by providing the elastic member 11 on the surface. The leak-proof flap 10 is composed of a leak-proof flap 10A on one side in the width direction x and a leak-proof flap 10B on the other side.

In the central flap 7 and the leak-proof flap 10, the distance between the standing base of the central flap 7A (or 7B) and the standing base of the leak-proof flap 10A (or 10B) is such that the distance between the standing base of the central flap 7A on one side and the standing base of the other is the other. It is provided so as to be longer than the distance between the side central flap 7B and the upright base. By providing the central flap 7 and the leak-proof flap 10 in this way, the central flap 7 can cover a wider range of the bellows portion 5. Further, since the leak-proof flap 10 is provided outside the width direction x of the absorbent article 1B, the absorbent core 4 can contribute to the absorption of urine and the like in a wide range in the width direction x, and is leak-proof. The flap 10 effectively prevents lateral leakage of urine and the like.

Although the configuration example of the absorbent article of the present invention has been described above, the absorbent article of the present invention can be modified in various ways to the above configuration example. For example, a recess may be formed in the absorbent core 4 instead of the opening 6. Further, in FIGS. 2 and 5, the elastic member 8 is attached to one surface of the center sheet 9 (lower surface in the drawing), and the elastic member 11 is attached to one surface of the side sheet 12 (lower surface in the drawing). Although it is attached, the center sheet 9 and the side sheet 12 may be formed into a multi-layer structure, and the elastic member 8 and the elastic member 11 may be provided between the layers. Other elastic members can also be arbitrarily arranged or removed.

1,1A, 1B: Absorbent article 2: Top sheet 3: Back sheet 4: Absorbent core 5: Bellows part, 5A: Mountain part, 5B: Valley part 6: Opening 7: Central flap 8,11,13,14 : Elastic member 10: Leakage-proof flap

Claims (9)

An absorbent article having a width direction and a front-rear direction, and having an absorbent core provided between a top sheet and a back sheet.
The absorbent core contains at least pulp fibers, has a basis weight of 100 g / m ² or more and 400 g / m ² or less, and is formed in a bellows shape having peaks and valleys alternately in the front-rear direction together with the top sheet. , The bellows are formed so that adjacent peaks or valleys can be deployed in the front-rear direction.
The top sheet is provided with a central flap on one side and the other side in the width direction, which is tilted outward in the width direction and overlaps with at least a part of the bellows-shaped absorbent core. An absorbent article characterized by. Claim 1 in which the length L1 in the anteroposterior direction in a bellows-shaped state of the absorbent core is 0.5 times or more and 0.9 times or less the length L2 in the anterior-posterior direction in a state in which the bellows are spread. Absorbent article described in. The absorbent article according to claim 1 or 2, wherein the distance between the upright base of the central flap on one side and the upright base of the central flap on the other side is 60 mm or less. The absorbent article according to any one of claims 1 to 3, wherein the central flap is provided with an elastic member extending in the front-rear direction. The absorbent article according to any one of claims 1 to 4, wherein a plurality of elastic members extending in the front-rear direction are provided side by side in the width direction on the central flap. The absorbent article according to any one of claims 1 to 5, wherein the central flap is made of a liquid-permeable non-woven fabric. The absorbent core according to any one of claims 1 to 6, wherein an opening or a recess extending in the front-rear direction is formed between the central flap on one side and the central flap on the other side. Goods. The absorbent article according to any one of claims 1 to 7, wherein a leak-proof flap tilted inward in the width direction is provided on the outside in the width direction of the central flap. The distance between the central flap and the leak-proof flap is such that the distance between the standing base of the central flap and the standing base of the leak-proof flap is the standing base of the central flap on one side and the standing base of the central flap on the other side. The absorbent article according to claim 8, which is provided so as to be longer than the distance between the two.

Images