CN111867536B

CN111867536B - Absorbent article

Info

Publication number: CN111867536B
Application number: CN201880091433.9A
Authority: CN
Inventors: 松井纱惠子; 林俊久; 山本成海; 内田祥平
Original assignee: Unicharm Corp
Current assignee: Unicharm Corp
Priority date: 2018-03-20
Filing date: 2018-03-20
Publication date: 2022-04-08
Anticipated expiration: 2038-03-20
Also published as: WO2019180827A1; TW201940144A; KR102475638B1; JP2019162298A; KR20200130725A; CN111867536A; TWI798389B; JP6356369B1

Abstract

The invention provides an absorbent article which can improve wearing feeling by reducing stuffiness degree and can inhibit leakage of body fluid by continuously wearing the absorbent article at a proper position relative to the body. An absorbent article (1) is provided with: a length direction (L) and a width direction (W) which are orthogonal to each other; a liquid-permeable surface sheet (10); a breathable and liquid-impermeable back sheet (20); an absorbent body (30) having at least pulp (31) and a super absorbent polymer (32); and an adhesive section (50) disposed on the non-skin-facing surface of the back sheet. The outer edge of the absorbent body is located inward of the outer edge of the absorbent article. An overlapping part (P1) in which a super absorbent polymer and an adhesive part are arranged in an overlapping manner in the thickness direction is provided in an outer Region (RO) between the outer edge of the absorbent body and the outer edge of the absorbent article.

Description

Absorbent article

Technical Field

The present invention relates to an absorbent article to be worn on underwear such as a sanitary pad or a light incontinence pad.

Background

Conventionally, absorbent articles that are worn on underwear and absorb body fluids such as leucorrhea, sweat, and urine have been used. The absorbent article of patent document 1 includes: a surface sheet; a back sheet; an absorber disposed between the front sheet and the back sheet, and having at least pulp and a super absorbent polymer; and an adhesive section disposed on the non-skin-facing surface of the back sheet. The back sheet of patent document 1 is made of a film having non-air permeability or air permeability (paragraph 0019 of patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2015-154881

Disclosure of Invention

Patent document 1 describes that the degree of stuffiness can be reduced by forming the back sheet with a breathable film. However, an adhesive portion is provided on the non-skin-facing surface of the back sheet, and moisture may reach the adhesive portion through the breathable back sheet. When the moisture reaches the adhesive portion, the adhesive force of the adhesive portion may be weakened. Therefore, there are cases where: the absorbent article is accidentally displaced relative to the undergarment and cannot be continuously worn in place relative to the body, thereby causing leakage of bodily fluids.

Therefore, an absorbent article is desired which can reduce the degree of stuffiness to improve the wearing feeling and which can suppress leakage of bodily fluids by being continuously worn at an appropriate position with respect to the body.

An absorbent article according to one aspect includes: a length direction and a width direction orthogonal to each other; a liquid-permeable surface sheet; a breathable and liquid-impermeable back sheet; an absorber disposed between the front sheet and the back sheet and having at least pulp and a super absorbent polymer; and an adhesive section disposed on a non-skin-facing surface of the back sheet, wherein an outer edge of the absorbent body is located inward of an outer edge of the absorbent article, and an overlapping section in which the super absorbent polymer and the adhesive section are arranged to overlap in a thickness direction is provided in an outer region between the outer edge of the absorbent body and the outer edge of the absorbent article.

Drawings

Fig. 1 is a plan view of the absorbent article of the embodiment as viewed from the skin-facing surface side.

Fig. 2 is a plan view of the absorbent article shown in fig. 1, as viewed from the non-skin-facing surface side.

Fig. 3 is a schematic sectional view taken along the a-a section of the absorbent article shown in fig. 1.

Fig. 4 is a schematic sectional view taken along the B-B section of the absorbent article shown in fig. 1.

Detailed Description

(1) Brief description of the embodiments

At least the following matters will be made clear from the description of the present specification and the drawings.

According to this embodiment, the super absorbent polymer is disposed in the region where the absorbent body is disposed and in the outer region. Therefore, even when urine is discharged beyond the absorbent body, the superabsorbent polymer in the outer region can hold the urine and the like. Further, since the back sheet has air permeability, moisture is easily discharged to the outside of the absorbent article through the back sheet when urine or sweat is absorbed. Therefore, the degree of stuffiness can be reduced to improve the wearing feeling. An overlapping portion in which the super absorbent polymer and the adhesive portion overlap in the thickness direction is provided in the outer region. When the body fluid reaches the overlapping portion, the body fluid is held by the super absorbent polymer, and the body fluid hardly reaches the back sheet. Therefore, moisture from the back sheet side is less likely to reach the adhesive portion in the overlapping portion, and the adhesive force can be maintained. Can be continuously worn at an appropriate position on the body, and leakage of body fluid can be suppressed.

According to a preferred aspect, a non-arrangement portion in which the super absorbent polymer and the adhesive portion are not arranged may be provided in the outer region.

According to this aspect, since the non-disposed section does not include the super absorbent polymer and the adhesive section, the air permeability is higher than that of the section where the super absorbent polymer is disposed and the section where the adhesive section is disposed. The non-arranged portion can ensure air permeability. The stuffiness degree can be further reduced, and the wearing feeling can be improved.

In the absorbent article relating to the other aspect, a polymer arrangement portion in which the superabsorbent polymer is arranged and the adhesive portion is not arranged may be provided in the outer region.

According to this embodiment, the polymer arrangement part is a part which does not have an adhesive part and is easily moved relative to the underwear, and therefore the super absorbent polymer is easily deformed (swollen). The super absorbent polymer disposed in the polymer disposition portion is more likely to swell than the super absorbent polymer disposed in the overlap portion, and the absorption performance of body fluid can be ensured.

According to a preferred aspect, an adhesive arrangement portion in which the adhesive portion is arranged and the super absorbent polymer is not arranged may be provided in the outer region, and the adhesive arrangement portion and the polymer arrangement portion may be adjacent to each other in a plan view.

According to this aspect, the super absorbent polymer in the polymer arrangement portion can absorb not only the body fluid that reaches the polymer arrangement portion but also the moisture in the periphery. Therefore, moisture of the adhesive arrangement portion adjacent to the polymer arrangement portion can be reduced. The adhesive arrangement portion can allow air to pass therethrough without passing moisture, and can maintain the adhesive force of the adhesive portion.

According to a preferred aspect, the outer region may have a 1 st region on the absorbent side and a 2 nd region on the outer edge side of the absorbent article, and the density of the super absorbent polymer in the 1 st region may be higher than the density of the super absorbent polymer in the 2 nd region.

According to this embodiment, the region 1 can hold a body fluid in which the superabsorbent polymer has a high density and the absorbent body does not hold the superabsorbent polymer completely. The 2 nd region is in contact with a region which is separated from the excretion portion and is easy to sweat. The 2 nd region can reliably absorb sweat having a moisture discharge amount smaller than that of excrement. In addition, since the superabsorbent polymer in the 2 nd region has a low density, it is possible to reduce the unpleasant feeling to the skin due to the unevenness when the superabsorbent polymer swells.

According to a preferred aspect, the absorber may include: a central region including a center of the absorber in the thickness direction; and a surface side region located on the outer side in the thickness direction than the central region, wherein the density of the super absorbent polymer in the central region is higher than the density of the super absorbent polymer in the surface side region.

According to a preferred aspect, the absorbent body may have a higher degree of hydrophilicity on the skin-facing surface side than on the non-skin-facing surface side.

According to this aspect, since the skin-facing surface side of the absorbent body has a high degree of hydrophilicity, the body fluid excreted into the topsheet can be rapidly absorbed, and the body fluid can be retained by the superabsorbent polymer in the absorbent body. Further, since the non-skin-facing surface side of the absorbent body has low hydrophilicity, it is difficult for body fluid absorbed in the body to reach the back sheet. Therefore, the moisture of the body fluid hardly reaches the adhesive portion, and the decrease in the adhesive force due to the arrival of the moisture can be suppressed, and the distortion of the absorbent article can be suppressed.

According to this embodiment, the superabsorbent polymer in the central region has a high density, and the central region is likely to swell upon absorption of body fluid. Therefore, the absorption capacity of the body fluid can be ensured. In addition, the superabsorbent polymer in the surface side region has a low density, and the surface side region is less likely to swell upon absorption of body fluid. Since the irregularities due to swelling of the super absorbent polymer are difficult to form in the front side region, the irregularities of the absorbent body are difficult to be transferred to the front sheet and the back sheet located outside the absorbent body in the thickness direction. The discomfort caused by the transmission of the irregularities to the front sheet and the back sheet during wearing can be reduced.

According to a preferred aspect, a pressing portion that compresses at least the front sheet and the back sheet in the thickness direction may be provided in the outer region, and the pressing portion may be disposed along an outer edge of the absorbent article.

According to this aspect, even if the body fluid reaches the squeezing portion, the body fluid diffuses in the squeezing portion having a high density, and the body fluid hardly reaches the outer side of the squeezing portion.

According to a preferred aspect, the front sheet, the back sheet, and the adhesive portion may be compressed in the thickness direction at the pressing portion.

According to this aspect, since the back sheet, the front sheet, and the adhesive portion are compressed together, the back sheet and the adhesive portion enter the recess formed by the pressing portion, and therefore, even if moisture reaches the adhesive portion, the adhesiveness is reduced, and the adhesive portion and the back sheet are less likely to be peeled off.

According to a preferred aspect, the back sheet may have a higher elongation strength than the top sheet.

According to this aspect, the back sheet is less likely to stretch and to be thinner when the pressing portion is formed. Therefore, moisture is less likely to permeate through the pressing portion, and a decrease in strength of the adhesive portion due to the arrival of moisture can be suppressed. Further, since the back sheet has low elongation strength, the height of the irregularities formed by the pressing portion on the back sheet side is lower than the height of the irregularities formed by the pressing portion on the front sheet side. Therefore, the gap between the undergarment and the back sheet can be reduced, and the absorbent article can be stably fixed to the undergarment.

According to a preferred aspect, a ratio of the elongation strength of the back sheet in the width direction to the elongation strength of the back sheet in the longitudinal direction may be 0.7 or more and 1.3 or less.

According to this aspect, the variation in the longitudinal direction elongation strength and the width direction elongation strength of the back sheet is small, and the back sheet is less likely to sag in the thickness direction when the pressed portion is formed. Therefore, the gap between the undergarment and the back sheet can be reduced, and the absorbent article can be stably fixed to the undergarment.

According to a preferred aspect, both the longitudinal elongation strength of the back sheet and the width elongation strength of the back sheet may be 2.0N/25mm or more.

According to this aspect, the longitudinal elongation strength of the back sheet and the width-directional elongation strength of the back sheet are stronger than the force applied to the back sheet when the absorbent article is peeled from the undergarment, and accidental breakage of the back sheet can be suppressed.

According to a preferred aspect, the absorbent article may include: a 3 rd region located at the center in the longitudinal direction; and a 4 th region located on the outer side in the longitudinal direction than the 3 rd region, wherein a maximum width in the width direction of the 4 th region is longer than a maximum width in the width direction of the 3 rd region, the pressing portion of the 4 th region has a wide width portion whose length in the width direction is longer than a length in the width direction of the pressing portion of the 3 rd region, and the wide width portion is provided at a position of the maximum width of the 4 th region.

The outer edge of the absorbent article having the maximum width of the 4 th region is likely to be subjected to an external force such as leg force. Since the wide portion is provided at the maximum width position, the rigidity at the maximum width position can be increased by the wide portion of the pressing portion, and the absorbent article can be prevented from being twisted or displaced from the underwear by an external force.

According to a preferred aspect, the plurality of adhesive portions may be provided so as to extend in the width direction and be spaced apart from each other in the longitudinal direction, and the adhesive portion located outermost in the longitudinal direction may overlap with the wide width portion in the width direction.

The adhesive part located outermost in the longitudinal direction is easily subjected to a force in the longitudinal direction from the body or underwear. Since the adhesive portion overlaps the wide portion in the width direction, the rigidity of the adhesive portion located outermost can be increased by the wide portion of the pressing portion, and it is possible to suppress a problem that the absorbent article is twisted or displaced from the underwear by an external force.

According to a preferred aspect, the adhesive part located outermost in the longitudinal direction may reach an outer edge of the absorbent article and overlap the wide width part in the thickness direction.

According to this aspect, the rigidity of the adhesive portion located outermost can be further increased by the wide portion of the pressing portion, and the absorbent article can be prevented from being twisted or displaced from the undergarment by an external force.

According to a preferred aspect, an adhesive section applied with an adhesive for adhering the front sheet and the back sheet may be provided on a skin-facing surface of the back sheet in the outer region.

According to this aspect, the super absorbent polymer is bonded to the back sheet by the bonding portion on the back sheet side. The body fluid can be retained immediately before the body fluid reaches the adhesive portion provided on the back sheet, and the adhesive force of the adhesive portion can be more easily maintained. Further, since the super absorbent polymer and the surface sheet are not bonded, a space where the super absorbent polymer swells is easily formed on the surface sheet side, and the super absorbent polymer easily swells.

According to a preferred aspect, an adhesive section applied with an adhesive for adhering the front sheet and the back sheet may be provided on the non-skin-facing surface of the front sheet in the outer region.

According to this aspect, the super absorbent polymer is bonded to the topsheet by the adhesive portion on the topsheet side. Therefore, the bodily fluid that has permeated through the topsheet can be absorbed immediately on the topsheet side. Further, since the super absorbent polymer is not bonded to the back sheet, a space in which the super absorbent polymer swells is easily formed on the back sheet side, and the super absorbent polymer easily swells.

(2) General structure of absorbent article

Hereinafter, an absorbent article according to an embodiment will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the scale of each dimension and the like are different from those in reality. Therefore, specific dimensions and the like should be determined with reference to the following description. In addition, the drawings may include portions having different dimensional relationships and ratios from each other.

The absorbent article is a sanitary pad. The absorbent article of the present invention may be any absorbent article used by wearing it on underwear, and may be, for example, a light incontinence pad. Fig. 1 is a plan view of the absorbent article 1 according to the present embodiment as viewed from the skin-facing surface side. Fig. 2 is a plan view of the absorbent article shown in fig. 1, as viewed from the non-skin-facing surface side. Fig. 3 is a schematic sectional view taken along the a-a section of the absorbent article shown in fig. 1. Fig. 4 is a schematic sectional view taken along the B-B section of the absorbent article shown in fig. 1.

The absorbent article 1 has a longitudinal direction L and a width direction W orthogonal to each other. The longitudinal direction L is defined by a direction extending to the front side and the back side of the body. In other words, the longitudinal direction L is a direction extending in the front-rear direction in the unfolded absorbent article 1. The absorbent article 1 has a thickness direction T orthogonal to both the longitudinal direction L and the width direction W. The thickness direction T extends toward a skin-facing surface side T1 of the wearer and a non-skin-facing surface side T2 opposite to the skin-facing surface side.

The absorbent article 1 has at least a top sheet 10, a back sheet 20, and an absorber 30. The top sheet 10 may be a liquid-permeable sheet such as a nonwoven fabric or an apertured plastic film. The front sheet 10 may be formed by stacking a plurality of sheets, or may have an auxiliary sheet. For example, the top sheet 10 may be formed of a skin surface side sheet formed by laminating a cotton sheet containing cotton fibers and a sheet formed of rayon and polyethylene, or the top sheet 10 may be formed of the skin surface side sheet and an auxiliary sheet formed of a through-air non-woven fabric. The top sheet 10 of the present embodiment is made of a hot air nonwoven fabric. More preferably, the absorbent-side surface of the top sheet 10 may be made of a through-air nonwoven fabric. The air-through nonwoven fabric has relatively large gaps between fibers, and the super absorbent polymer of the absorber described later is easily and uniformly arranged. Therefore, the super absorbent polymer is likely to swell throughout the entire absorbent article, and the absorption performance can be improved.

The back sheet 20 may be made of a breathable and liquid-impermeable sheet such as a plastic film. Since the back sheet 20 has breathability, moisture is easily discharged to the outside of the absorbent article through the back sheet 20 when urine or sweat is absorbed. Therefore, the degree of stuffiness can be reduced to improve the wearing feeling. The top sheet 10 and the back sheet 20 reach the outer edge of the absorbent article. In the present embodiment, the outer edge is an outer end in the width direction W, the front edge is a front edge, and the rear edge is a rear edge. The outer edge is an entire outer peripheral edge including the outer edge, the front edge, and the rear edge.

An adhesive section 50 for wearing the absorbent article 1 on underwear is disposed on the non-skin-facing surface of the back sheet 20. The plurality of adhesive portions 50 extend in the width direction W and are provided at intervals in the longitudinal direction L. The adhesive portion 50 may reach the outer edge 1E of the absorbent article 1. The adhesive part 50 has an adhesive part 51 located outermost in the longitudinal direction L. The adhesive portion 51 located outermost in the longitudinal direction L may be located outward in the longitudinal direction L from the maximum width PM of the absorbent article 1. The maximum width PM of the absorbent article is the maximum width of the 4 th region described later. In the modification, the adhesive portions 50 may be arranged to extend in the longitudinal direction L and to be spaced apart from each other in the width direction W.

The absorber 30 is disposed between the front sheet 10 and the back sheet 20. The absorber 30 includes at least absorbent materials such as pulp 31 and Super Absorbent Polymer (SAP) 32. The absorber has pulp, and can absorb the white band by the pulp. The absorbent body also has a super absorbent polymer 32, and urine and sweat can be absorbed by the super absorbent polymer 32. The absorbent body 30 may be a sheet-like absorbent body. The absorber 30 may also have a core cladding that covers the absorbent material. As shown in fig. 3, the absorber 30 has: a central region RC including the center of the absorber in the thickness direction; and a front surface region RS located outside the central region RC in the thickness direction T. The front surface regions RS are provided on the skin facing surface side T1 and the non-skin facing surface side T2 of the central region RC, respectively. The boundary between the front region RS and the central region RC is a boundary that trisects the absorber 30 in the thickness direction.

The outer edge 30E of the absorber 30 is located inward of the outer edge 1E of the absorbent article 1. That is, the front end edge 30F of the absorbent body 30 is located on the rear side of the front end edge 1F of the absorbent article 1, the rear end edge 30R of the absorbent body 30 is located on the front side of the rear end edge 1R of the absorbent article 1, and the outer edge 30S of the absorbent body 30 is located on the inner side in the width direction W than the outer edge 1S of the absorbent article 1. An outer region RO is provided between the outer edge 30E of the absorbent body 30 and the outer edge 1E of the absorbent article 1. The outer region RO is a region marked with diagonal lines in fig. 1. The front sheet 10 and the back sheet 20 are disposed in the outer region RO. In the outer region RO, the pulp 31 is not disposed, and the super absorbent polymer 32 is disposed. The super absorbent polymer 32 is disposed in the region where the absorbent body is disposed and in the outer region. Therefore, even when urine is discharged beyond the absorbent body, the superabsorbent polymer 32 can hold the urine and the like. Further, the super absorbent polymer 32 can adsorb ammonia components dissolved in water and gaseous ammonia, and can also reduce odor.

The absorbent article of the present embodiment is used for a long period of time as a sanitary pad. The pulp absorbs body fluid such as leucorrhea and sweat, and the super absorbent polymer 32 also absorbs body fluid due to light incontinence. The absorbent article of the present embodiment can absorb not only the white band but also urine, and can discharge moisture to the outside by the breathable back sheet 20, thereby maintaining a dry wearing feeling.

Fig. 4 is a view schematically showing a cross section of the absorbent article in the outer region RO. In the outer region RO, a superposed portion P1 is provided in which the super absorbent polymer 32 and the adhesive portion 50 are superposed in the thickness direction T. In the overlapping portion P1, the front sheet 10, the super absorbent polymer 32, the back sheet 20, and the adhesive portion 50 are arranged from the skin facing surface side T1 toward the non-skin facing surface side T2. When the body fluid reaches the overlapping portion P1, the body fluid is held by the super absorbent polymer 32, and the body fluid hardly reaches the back sheet 20. Therefore, the moisture from the back sheet 20 side of the adhesive portion 50 in the overlapping portion P1 is hard to reach, and the adhesive force can be maintained. The adhesive force of the adhesive portion 50 can be maintained at the overlapping portion P1, and the absorbent article 1 can be suppressed from being accidentally displaced with respect to the undergarment. Can be continuously worn at an appropriate position on the body, and leakage of body fluid can be suppressed. Therefore, the wearing feeling is improved by reducing the degree of stuffiness, and leakage of body fluid can be suppressed by continuously wearing the garment at an appropriate position with respect to the body.

The non-disposed portion P2 where the super absorbent polymer 32 and the adhesive portion 50 are not disposed may be provided in the outer region RO. In the non-placement section P2, the front sheet 10 and the back sheet 20 are placed from the skin facing surface side T1 toward the non-skin facing surface side T2. The non-disposed portion P2 has higher air permeability than the portion where the super absorbent polymer 32 is disposed and the portion where the adhesive portion 50 is disposed, because the super absorbent polymer 32 and the adhesive portion 50 are not disposed. The non-arrangement portion P2 can ensure air permeability. The stuffiness degree can be further reduced, and the wearing feeling can be improved.

The polymer arrangement parts P3 in which the super absorbent polymer 32 is arranged and the adhesive parts 50 are not arranged may be provided in the outer region RO. In the polymer arrangement portion P3, the front sheet 10 and the back sheet 20 are arranged from the skin-facing surface side T1 toward the non-skin-facing surface side T2. Since the adhesive part 50 is not disposed in the polymer disposition part P3, it is a part that moves relatively easily without being joined to underwear, and the super absorbent polymer 32 is easily deformed (swelled). The super absorbent polymer 32 disposed in the polymer disposition portion is more likely to swell than the super absorbent polymer 32 disposed in the overlap portion, and the absorption performance of the body fluid can be further ensured.

In the outer region RO, an adhesive arrangement portion P4 may be provided in which the adhesive portion 50 is arranged and the super absorbent polymer 32 is not arranged. In the adhesive arrangement portion P4, the front sheet 10, the back sheet 20, and the adhesive portion 50 are arranged from the skin facing surface side T1 toward the non-skin facing surface side T2. The polymer arrangement portion P3 may be adjacent to at least one of the adhesive arrangement portion P4 and the non-arrangement portion P2 in a plan view. The super absorbent polymer in the polymer arrangement part P3 can absorb not only the body fluid that has reached the polymer arrangement part P3 but also the surrounding moisture. Therefore, moisture in the adhesive arrangement portion P4 and the non-arrangement portion P2 adjacent to the polymer arrangement portion P3 can be reduced. With such a configuration, air can be prevented from permeating through the adhesion arrangement portion P4 by moisture, and the adhesion force of the adhesion portion 50 can be maintained.

The outer region RO may be provided with a pressing portion 60 formed by compressing the front sheet 10 and the back sheet 20 in the thickness direction T. The pressing portion 60 may be provided along the outer edge 1E of the absorbent article 1. The plurality of squeezing portions 60 may be provided inside the outer edge 1E of the absorbent article 1, and may be arranged along the outer edge 1E at intervals. By providing the squeezing portion 60, even if the body fluid reaches the squeezing portion 60 of the outer region RO, the body fluid is diffused in the squeezing portion 60 having a high density, and therefore, the body fluid is hard to reach a position outside the squeezing portion 60. In addition, the non-disposed portions and the adhesive disposed portions of the outer region RO do not have the super absorbent polymer 32 disposed, and the back sheet or the like is less likely to be damaged when the compressed portions 60 are formed. Therefore, it is possible to secure adhesiveness to underwear or suppress leakage of body fluid due to breakage of the sheet.

In the pressing portion 60, the front sheet 10, the back sheet 20, and the adhesive portion 50 may be compressed in the thickness direction. Since the back sheet 20, the front sheet 10, and the adhesive section 50 are compressed together and enter the concave portion in which the adhesive section 50 is formed together with the back sheet 20, even if moisture reaches the adhesive section 50, the adhesiveness is lowered, and the adhesive section 50 and the back sheet 20 are difficult to be peeled.

The back sheet 20 may have a higher elongation strength than the top sheet 10. More preferably, the back sheet 20 may have a higher elongation strength than other materials (topsheet, absorbent body, etc.) constituting the absorbent article. The elongation strength is a value indicating the difficulty of stretching of the sheet in the planar direction, and can be measured by the following measurement method. The test was carried out using (1) a tensile tester and (2) a die (rectangular die 44 mm. times.width 25 mm). As a procedure, first, a test piece is prepared. The test piece was prepared by immersing the absorbent article in toluene, dividing the absorbent article into a front sheet and a back sheet, and punching the sheet to be measured with a punching die at a size of 45mm × 25 mm. The test piece was provided with a grip at a portion ranging from both ends in the longitudinal direction (45mm) to a length of 7mm so that the distance between the grips was 30mm in the center of the test piece. The holding part was made of an aluminum tape 50mm in length and 30mm in width, and the test piece was held from both sides. Then, with the collet spacing: 30mm, stretching speed: the measurement was carried out at 500 mm/min. The strength at 5% elongation (N/25mm) and the maximum elongation strength (N/25mm) in the longitudinal direction and the width direction, respectively, were measured.

The relationship between the elongation strength of the front sheet and the elongation strength of the back sheet in the present invention is defined as follows. When the 5% elongation strength of the front sheet in the longitudinal direction is higher than the 5% elongation strength of the back sheet in the longitudinal direction and the 5% elongation strength of the front sheet in the width direction is higher than the 5% elongation strength of the back sheet in the width direction, the elongation strength of the front sheet 10 is set to be higher than the elongation strength of the back sheet. On the other hand, in the case where the elongation strength of 5% in the longitudinal direction of the front sheet is higher than the elongation strength of 5% in the longitudinal direction of the back sheet and the elongation strength of 5% in the width direction of the front sheet is lower than the elongation strength of 5% in the width direction of the back sheet, and in the case where the elongation strength of 5% in the longitudinal direction of the front sheet is lower than the elongation strength of 5% in the longitudinal direction of the back sheet and the elongation strength of 5% in the width direction of the front sheet is lower than the elongation strength of 5% in the width direction of the back sheet, and when the 5% elongation strength of the front sheet in the longitudinal direction is lower than the 5% elongation strength of the back sheet in the longitudinal direction and the 5% elongation strength of the front sheet in the width direction is higher than the 5% elongation strength of the back sheet in the width direction, the elongation strength of the back sheet 20 is higher than the elongation strength of the front sheet 10.

Since the back sheet 20 has higher elongation strength than the front sheet 10, the back sheet 20 is less likely to elongate and the back sheet 20 is less likely to be thin when the pressed portion 60 is formed. Therefore, moisture is less likely to permeate through the pressing portion 60, and the strength of the adhesive portion 50 can be prevented from being reduced by the arrival of moisture. Further, since the back sheet 20 has high elongation strength and is hard to elongate, the height of the irregularities formed by the pressed portion on the back sheet 20 side is lower than the height of the irregularities formed by the pressed portion on the front sheet 10 side. Therefore, the gap between the undergarment and the back sheet can be reduced, and the absorbent article can be stably fixed to the undergarment. The front sheet of the present embodiment is configured to extend only in one of the longitudinal direction and the width direction, and the back sheet is configured to extend in both the longitudinal direction and the width direction. By being able to elongate in two directions, the elongation strength tends to be low.

The ratio of the elongation strength of the back sheet in the width direction to the elongation strength of the back sheet in the longitudinal direction may be 0.7 or more and 1.3 or less. More preferably, the ratio is 0.9 or more and 1.1 or less. The ratio of the elongation strength of the back sheet in the width direction to the elongation strength of the back sheet in the longitudinal direction is 0.7 or more and 1.3 or less, so that the variation between the elongation strength of the back sheet in the longitudinal direction and the elongation strength of the back sheet in the width direction is small, and the back sheet is less likely to sag in the thickness direction when the pressed portion is formed. Therefore, the gap between the undergarment and the back sheet can be reduced, and the absorbent article can be stably fixed to the undergarment.

The elongation strength of the back sheet in the longitudinal direction and the elongation strength of the back sheet in the width direction may be 2.0N/25mm or more, and more preferably 5.0N/25mm or more. When the elongation strength of the back sheet is 2.0N/25mm or more, the force applied to the back sheet when the absorbent article is peeled from the underwear is stronger, and the back sheet can be prevented from being accidentally broken.

As shown in fig. 3, the outer region RO has a 1 st region R1 on the absorbent body 30 side and a 2 nd region R2 on the outer edge 1E side of the absorbent article 1. The boundary between the 1 st region R1 and the 2 nd region R2 is the center between the outer edge 1E of the absorbent article 1 and the outer edge 30E of the absorbent body 30. The density of the superabsorbent polymer 32 in the 1 st region R1 may be higher than the density of the superabsorbent polymer 32 of the 2 nd region R2. The superabsorbent polymer 32 in the 1 st region R1 has a high density, and can hold a body fluid that is not completely held by the absorbent body 30. The 2 nd region R2 is in contact with a region that is separated from the excretory part and is likely to sweat. The 2 nd region R2 can reliably absorb sweat having a moisture discharge amount smaller than that of excrement. Further, since the density of the super absorbent polymer in the 2 nd region R2 is low, it is possible to reduce the feeling of discomfort on the skin due to the unevenness when the super absorbent polymer 32 swells. As a method for measuring the density, a test piece having the same area is cut in each of the 1 st region and the 2 nd region, and the superabsorbent polymer contained in the test piece is taken out and the weight is measured, whereby the density can be measured.

The density of the super absorbent polymer 32 in the outer region RO located outside the absorbent body 30 in the width direction W may be higher than the density of the super absorbent polymer 32 in the No. 2 region of the outer region RO located outside the absorbent body 30 in the longitudinal direction L. The outer region RO located on the outer side in the width direction W than the absorber 30 is likely to come into contact with the base of the wearer's leg. Moisture due to sweat or the like can be absorbed in the region in contact with the base of the leg which is relatively likely to sweat. As a method for measuring the density, similarly to the methods for measuring the 1 st and 2 nd regions, a test piece having the same area is cut out from each region, and the superabsorbent polymer contained in the test piece is taken out and the weight is measured, whereby the density can be measured.

The density of the superabsorbent polymer 32 may be constant or may vary within the absorbent body. As shown in fig. 3, the density of the super absorbent polymer 32 in the central region RC of the absorbent body 30 may be higher than the density of the super absorbent polymer 32 in the surface side region RS of the absorbent body 30. Since the density of the super absorbent polymer 32 in the central region is high, the central region RC is easily expanded upon absorption of body fluid. Therefore, the absorption capacity of the body fluid can be ensured. In addition, the density of the super absorbent polymer 32 in the front side region RS is low, and the front side region RS is hard to swell when absorbing body fluid. Since the irregularities due to swelling of the super absorbent polymer 32 are hardly formed in the front side region RS, the irregularities of the absorbent body are hardly transmitted to the front sheet 10 and the back sheet 20 located outside in the thickness direction of the absorbent body. It is possible to reduce the uncomfortable feeling at the time of wearing due to the transmission of the irregularities to the front sheet 10 and the back sheet 20. As a method for measuring the density, the following measurement can be performed: the absorbent article is cut in a cross section along the thickness direction, the cross section is photographed by electrophotography, the number of super absorbent polymers contained in the same area is measured in each region, and the density is increased as the number is increased.

The skin-facing surface side T1 of the absorbent body 30 may have a higher degree of hydrophilicity than the non-skin-facing surface side T2 of the absorbent body 30. Here, the degree of hydrophilicity means the strength with which the absorbent body absorbs water, and the force with which the absorbent body absorbs liquid becomes stronger on the side with a higher degree of hydrophilicity than on the side with a lower degree of hydrophilicity. Since the skin-facing surface side T1 of the absorbent body 30 has a high degree of hydrophilicity, the bodily fluid excreted into the topsheet 10 can be rapidly absorbed, and the bodily fluid can be retained by the super absorbent polymer 32 in the absorbent body 30. Further, since the non-skin-facing surface side T2 of the absorbent body 30 has a low degree of hydrophilicity, body fluid in the absorbent body 30 hardly reaches the back sheet 20. Therefore, the moisture of the body fluid hardly reaches the adhesive portion 50, and the decrease in the adhesive force due to the arrival of the moisture can be suppressed, and the distortion of the absorbent article can be suppressed.

As a method of making the degree of hydrophilicity of the absorbent body different in the thickness direction, for example, the absorbent body may be configured by 2 layers of an upper layer on the skin-facing surface side and a lower layer on the non-skin-facing surface side, and the degree of hydrophilicity of the adhesive for setting the absorbent material may be different depending on the upper layer and the lower layer. As the binder of the upper layer, a binder containing a hydrophilic agent is used, and as the binder of the lower layer, a binder containing no hydrophilic agent is used.

In addition, the degree of hydrophilicity can be measured by the following method. (1) 5 sheets of filter paper were horizontally placed in a superposed state, and a test piece to be measured was mounted on the filter paper. (2) The test piece was marked with marks at 2cm intervals in the longitudinal and transverse directions, respectively. 1 drop (about 0.05g) of artificial urine was dropped to 20 sites with a pipette. The artificial urine was dropped at 20 sites for 1 minute and 10 seconds. (3) After leaving for 30 seconds from the end of dropping of 20 sites, the sites absorbed by the test piece were counted. The more the test piece has absorbed the water content, the higher the hydrophilicity.

In the outer region RO, an adhesive section 70 coated with an adhesive for bonding the front sheet 10 and the back sheet 20 may be provided on the skin-facing surface of the back sheet 20. As the adhesive, for example, a hot-melt adhesive can be exemplified. The super absorbent polymer 32 is bonded to the back sheet 20 by a back sheet side bonding portion. The body fluid can be retained immediately before the body fluid reaches the adhesive portion 50 provided on the back sheet 20, and the adhesive force of the adhesive portion 50 can be more easily maintained. Further, since the super absorbent polymer 32 and the topsheet 10 are not bonded, a space in which the super absorbent polymer 32 swells is easily formed on the topsheet 10 side, and the super absorbent polymer 32 easily swells.

As shown in fig. 1, the absorbent article 1 has a 3 rd region R3 located at the center in the longitudinal direction L and a 4 th region R4 located outward in the longitudinal direction L from the 3 rd region. The boundary between the 3 rd region R3 and the 4 th region R4 is a boundary that bisects the absorbent article in the longitudinal direction L. The maximum width in the width direction W of the 4 th region is longer than the maximum width in the width direction W of the 3 rd region.

The pressing part 60 may be disposed across the 3 rd region R3 and the 4 th region R4. The squeeze part 60 of the 4 th region R4 has a wide width part 61 having a length in the width direction W longer than the squeeze part 60 in the 3 rd region R3. The wide portion 61 is a hatched area in fig. 2. In the 3 rd region R3 and the 4 th region R4, the squeezing portion 60 located inward of the wide width portion 61 in the longitudinal direction L is composed of a linear squeezing portion 65 formed by connecting a plurality of arcs, and a dot-shaped squeezing portion 66 located inward of the linear squeezing portion 65 and along the linear squeezing portion 60. That is, 2 rows of the pressing portions are arranged. On the other hand, dot-shaped pressing portions 66 arranged along the linear pressing portions 65 are provided on the wide portion 61 outside and inside the linear pressing portions 65 formed by connecting a plurality of arcs. That is, 3 rows of the pressing portions are arranged. The wide part 61 may be provided at a position of the maximum width PM of the 4 th region. The outer edge of the absorbent article having the maximum width of the 4 th region is likely to be subjected to an external force such as leg force. Since the wide portion 61 is provided at the maximum width position, the rigidity at the maximum width position can be increased by the wide portion 61 of the pressing portion 60, and the absorbent article can be prevented from being twisted or displaced from the underwear by an external force.

The wide portion 61 may overlap the adhesive portion 51 located outermost in the longitudinal direction L in the width direction W. The state of overlapping in the width direction W refers to a state in which the adhesive portion 51 is disposed on an extension line of the wide portion 61 extending in the width direction W. The adhesive part 51 located outermost in the longitudinal direction is easily subjected to a force along the longitudinal direction L from the body or underwear. Since the adhesive part 51 overlaps with the wide part 61 in the width direction W, the rigidity of the adhesive part 51 located outermost can be increased by the wide part 61 of the pressing part 60, and the problem that the absorbent article is twisted or displaced from the underwear by an external force can be suppressed.

More preferably, the adhesive part 51 located outermost in the longitudinal direction L may reach the outer edge 1E of the absorbent article and overlap the wide part 61 in the thickness direction T. The wide portion 61 of the pressing portion 60 can further increase the rigidity of the adhesive portion 50 located outermost, and can suppress the absorbent article from being twisted or displaced from the underwear by an external force.

The present invention has been described in detail with reference to the above embodiments, but it is obvious to those skilled in the art that the present invention is not limited to the embodiments described in the present specification. The present invention can be implemented as modifications and variations without departing from the spirit and scope of the present invention defined by the claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

For example, in the absorbent article of the modified example, an adhesive portion to which an adhesive for adhering the front sheet 10 and the back sheet 20 is applied may be provided on the non-skin-facing surface of the front sheet 10 in the outer region RO. The super absorbent polymer 32 is bonded to the topsheet 10 at the bonding portion on the topsheet 10 side. Therefore, the bodily fluid that has permeated through the top sheet 10 can be absorbed immediately on the top sheet 10 side. Further, since the super absorbent polymer 32 and the back sheet 20 are not bonded, a space in which the super absorbent polymer 32 swells is easily formed on the back sheet 20 side, and the super absorbent polymer 32 easily swells. In addition, when the non-skin-facing surface of the top sheet 10 is formed of a through-air nonwoven fabric, the superabsorbent polymer 32 easily enters the relatively bulky nonwoven fabric having large gaps between fibers. Therefore, a space for swelling can be more easily formed on the back sheet 20 side of the super absorbent polymer 32, and the absorption performance can be improved.

In addition, the entire contents of japanese patent application No. 2018-052339, filed on 3/20/2018, are incorporated herein by reference.

Industrial applicability of the invention

According to the present invention, it is possible to provide an absorbent article that can reduce the degree of stuffiness to improve the wearing feeling, and can suppress leakage of bodily fluids by being continuously worn at an appropriate position on the body.

Description of the reference numerals

1 absorbent article

10 surface sheet

20 back sheet

30 absorbent body

31 pulp

32 superabsorbent polymers

50 adhesive part

51 adhesive part located outermost in the longitudinal direction

60 extrusion part

61 wide part

70 bonding part

Outer region of RO

Region 1 of R1

Region 2 of R2

Region 3 of R3

Region 4 of R4

RC central region

RS surface side region

P1 overlap

P2 non-arrangement part

P3 Polymer arrangement

P4 adhesive arrangement part

Maximum width of PM

Claims

1. An absorbent article having a plurality of absorbent layers,

the absorbent article has:

a length direction and a width direction orthogonal to each other;

a liquid-permeable surface sheet;

a breathable and liquid-impermeable back sheet;

an absorber disposed between the front sheet and the back sheet and having at least pulp and a super absorbent polymer; and

an adhesive part disposed on the non-skin-facing surface of the back sheet,

it is characterized in that the preparation method is characterized in that,

the outer edge of the absorbent body is positioned inward of the outer edge of the absorbent article,

an outer region between an outer edge of the absorber and an outer edge of the absorbent article is provided with:

an overlapping portion formed by overlapping the super absorbent polymer and the adhesive portion in a thickness direction;

a polymer arrangement part in which the super absorbent polymer is arranged and the adhesive part is not arranged; and

an adhesive arrangement portion where the adhesive portion is arranged and the super absorbent polymer is not arranged,

the adhesive arrangement portion and the polymer arrangement portion are adjacent in a plan view.

2. The absorbent article according to claim 1,

in the outer region, an adhesive section is provided on a skin-facing surface of the back sheet, and an adhesive for adhering the front sheet and the back sheet is applied to the adhesive section.

3. The absorbent article according to claim 1,

in the outer region, an adhesive section is provided on a non-skin-facing surface of the front sheet, and an adhesive for bonding the front sheet and the back sheet is applied to the adhesive section.

4. The absorbent article according to claim 1,

the non-arrangement portion where the super absorbent polymer and the adhesive portion are not arranged is provided in the outer region.

5. The absorbent article according to claim 1,

the outer region has a 1 st region on the absorbent side and a 2 nd region on the outer edge side of the absorbent article,

the superabsorbent polymer of the 1 st zone has a higher density than the superabsorbent polymer of the 2 nd zone.

6. The absorbent article according to claim 1,

the absorbent body has: a central region including a center of the absorber in the thickness direction; and a front surface side region located on the outer side in the thickness direction than the central region,

the density of the superabsorbent polymer of the central region is higher than the density of the superabsorbent polymer of the surface side region.

7. The absorbent article according to claim 1,

the absorbent body has a higher degree of hydrophilicity on the skin-facing surface side than on the non-skin-facing surface side.

8. An absorbent article having a plurality of absorbent layers,

the absorbent article has:

a length direction and a width direction orthogonal to each other;

a liquid-permeable surface sheet;

a breathable and liquid-impermeable back sheet;

an adhesive part disposed on the non-skin-facing surface of the back sheet,

it is characterized in that the preparation method is characterized in that,

an overlapping portion formed by overlapping the super absorbent polymer and the adhesive portion in a thickness direction; and

a pressing portion formed by compressing at least the front surface sheet and the back surface sheet in the thickness direction,

the pressing portion is disposed along an outer edge of the absorbent article,

the front surface sheet, the back surface sheet, and the adhesive portion are compressed in the thickness direction at the pressing portion.

9. The absorbent article of claim 8,

the back sheet has a higher elongation strength than the front sheet.

10. The absorbent article of claim 9,

a ratio of an elongation strength of the back sheet in the width direction to an elongation strength of the back sheet in the longitudinal direction is 0.7 or more and 1.3 or less.

11. The absorbent article according to claim 9 or 10,

the back sheet has an elongation strength in the longitudinal direction and an elongation strength in the width direction of 2.0N/25mm or more.

12. The absorbent article according to any one of claims 8 to 10,

the absorbent article has: a 3 rd region located at the center in the longitudinal direction; and a 4 th region located on the outer side in the longitudinal direction than the 3 rd region,

a maximum width in the width direction of the 4 th region is longer than a maximum width in the width direction of the 3 rd region,

the pressing portion of the 4 th region has a wide width portion having a length in the width direction longer than a length in the width direction of the pressing portion of the 3 rd region,

the wide width part is provided at the position of the maximum width of the 4 th region.

13. The absorbent article of claim 12,

the plurality of adhesive parts extend along the width direction and are arranged at intervals in the length direction,

the adhesive portion located outermost in the longitudinal direction overlaps with the wide width portion in the width direction.

14. The absorbent article of claim 13,

the adhesive portion located outermost in the longitudinal direction reaches an outer edge of the absorbent article, and overlaps with the wide width portion in the thickness direction.

15. The absorbent article of claim 8,

16. The absorbent article of claim 8,

17. The absorbent article of claim 8,

18. The absorbent article of claim 8,

19. The absorbent article of claim 8,

20. The absorbent article of claim 8,