WO2012132617A1

WO2012132617A1 - Absorbent article

Info

Publication number: WO2012132617A1
Application number: PCT/JP2012/053862
Authority: WO
Inventors: 規世子西村; 俊幸谷尾
Original assignee: ユニ・チャーム株式会社
Priority date: 2011-03-30
Filing date: 2012-02-17
Publication date: 2012-10-04
Also published as: JP5939739B2; JP2012205859A

Abstract

The purpose of the present invention is to provide an absorbent article having both of good durability in use and excellent hydrolyzable properties after discharge. The configuration of the disclosed absorbent article is as follows. The hydrolyzable absorbent article, which comprises a front surface sheet, a back surface sheet and an absorbent sheet that is positioned between the front surface sheet and the back surface sheet, is characterized in that the front surface sheet is formed of a spun lace non-woven fabric, the absorbent sheet is formed of an airlaid non-woven fabric containing a water-soluble binder, the front surface sheet is adhered to the absorbent sheet and thus integrated therewith, and the integrated front surface sheet and absorbent sheet have a plurality of openings.

Description

Absorbent articles

The present disclosure relates to an absorbent article in which the integrated topsheet and absorbent sheet have a plurality of openings.

An absorbent article having water decomposability, for example, a sanitary napkin, a panty liner, a urine removing pad, etc. having water decomposability have been developed and are commercially available. These absorbent articles are made of a material having water decomposability, and are designed to disperse in water when flowing into a large amount of water such as a flush toilet.

For example, Patent Document 1 discloses an absorbent article having a liquid-permeable surface layer, a liquid-impermeable leak-proof layer, and a liquid-retaining absorbent layer, wherein a part of the absorbent layer is the above-mentioned An absorbent article is described which extends to the peripheral edge of the absorbent article and the absorbent layer does not extend over the entire area of the peripheral edge of the absorbent article. The absorbent article described in Patent Document 1 has a design in which part of the absorbent layer of the absorbent article extends to the peripheral edge, and when discarded in water, separation between members is easily started. Has been made.

Patent Document 2 discloses an absorbent article having a liquid-permeable surface layer, a liquid-impermeable leak-proof layer, and a liquid-retaining absorbent layer, and at least the surface layer and the leak-proof layer. Are formed at the peripheral edge of the absorbent article. The joint is composed of a strong joint having a relatively large joint strength and a weak joint having a smaller joint strength than the strong joint. A water-disintegratable absorbent article comprising a part is described. In the absorbent article described in Patent Document 2, the joint part of the peripheral part of the absorbent article is composed of a strong joint part and a weak joint part, and separation between members starts from the weak joint part when discarded into water Is designed to make it easier to start.

Further, Patent Document 3 discloses a water-degradable absorptivity having a water-degradable back layer, a water-decomposable and liquid-permeable surface layer, and a water-degradable absorbent layer having a smaller plane dimension than the back layer and the surface layer. An outer peripheral region in which the back surface layer and the surface layer are overlapped without an absorbent layer is formed in an area having a predetermined width from the periphery of the absorbent article, and the thermoplastic water-soluble adhesive layer is The seal is provided on almost the entire surface in both the outer peripheral region and the intermediate region inside the outer peripheral region, and the back surface layer and the surface layer are heat-sealed via a thermoplastic water-soluble adhesive in the outer peripheral region. A water-decomposable absorbent article is described in which a portion is formed, and a missing portion is formed in at least a part of the seal portion. In the absorbent article described in Patent Document 3, the layers are easily separated from the outer peripheral region when disposed in the flush toilet by setting the interlayer bonding strength in the intermediate region to the interlayer bonding strength in the outer peripheral region. Designed to be

Further, Patent Document 4 discloses a water-degradable absorptivity having a water-degradable back layer, a water-decomposable and liquid-permeable surface layer, and a water-degradable absorbent layer having a smaller plane dimension than the back layer and the surface layer. In an intermediate region of the article, the absorbent layer and the back surface layer and / or the absorbent layer and the surface layer are bonded with a water-soluble or water-swellable adhesive, and the adhesive is dry and wet. There is described a water-decomposable absorbent article characterized in that the bonding strength between layers in the intermediate region bonded in (1) is higher than the bonding strength between layers in the outer peripheral region. The absorbent article described in Patent Document 4 has a missing portion in at least a part of the heat seal portion in the outer peripheral region, and the seal portion is likely to dissociate from that point, and further, air escapes therefrom and sinks into the septic tank. Designed to be easy.

JP 2002-143219 A JP 2002-209930 A JP 2001-190596 A JP 2001-190590 A

The absorbent articles described in Patent Documents 1 to 4 are designed to improve the separability when discarded in water by providing a separation starting point between members in a part of the product. However, since the separation starting point is also a portion where the adhesive strength of the absorbent article is weak, there is a problem from the viewpoint of durability during use. Moreover, in the said absorbent article, when the adhesive strength of another part is raised in order to supplement the low durability of a separation start point, there exists a tendency for the water disintegration of the part which raised the adhesive strength to be inferior. Therefore, the absorbent articles described in Patent Documents 1 to 4 have problems in either durability during use or water disintegration after disposal.
Therefore, this indication aims at providing the absorptive article which is excellent in both durability at the time of use, and water disintegration after disposal.

As a result of earnest studies to solve the above-mentioned problems, the present inventors have found that the absorbent article has water decomposability and includes a top sheet, a back sheet, and an absorbent sheet between the top sheet and the back sheet. The surface sheet is formed from a spunlace nonwoven fabric, the absorbent sheet is formed from an airlaid nonwoven fabric containing a water-soluble binder, and the surface sheet is integrated by being bonded to the absorbent sheet. It has been found that the above problems can be solved by an absorbent article characterized in that the integrated topsheet and absorbent sheet have a plurality of openings.

The absorbent article of the present disclosure is excellent in both durability during use and water disintegration after disposal.

Drawing 1 is a figure which looked at one of the embodiments of an absorptive article of this indication from the surface sheet side. FIG. 2 is a cross-sectional view of the region X ′ of the absorbent article 1 shown in FIG. FIG. 3 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure. FIG. 4 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure. FIG. 5 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure.

Drawing 6 is a figure which looked at another embodiment of an absorptive article of this indication from the surface sheet side. Drawing 7 is a figure which looked at another embodiment of an absorptive article of this indication from the surface sheet side. FIG. 8 is a view of another embodiment of the absorbent article of the present disclosure as viewed from the topsheet side. FIG. 9 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure.

The absorbent article of the present disclosure will be described in detail below.
Drawing 1 is a figure which looked at one of the embodiments of an absorptive article of this indication from the surface sheet side. FIG. 2 is a cross-sectional view of the region X ′ of the absorbent article 1 shown in FIG.

An absorbent article 1 having water decomposability shown in FIGS. 1 and 2 is a panty liner having water decomposability, and includes a top sheet 2, a back sheet 3, and an absorbent sheet 4 between the top sheet 2 and the back sheet 3. Including. In the absorbent article 1 shown in FIGS. 1 and 2, the top sheet 2 is integrated by being bonded to the absorbent sheet 4, and the integrated top sheet and the absorbent sheet 5 have a plurality of openings. 6.
In addition, in this specification, in order to distinguish the opening part which the integrated surface sheet and absorption sheet have from the opening part which the below-mentioned back surface sheet has, it may be called a "first opening part".

The absorbent article 1 shown in FIGS. 1 and 2 further includes a leak-proof sheet 8 between the absorbent sheet 4 and the back sheet 3, and the top sheet 2, absorbent sheet 4 and It has the pressing part 7 formed by pressing the back surface sheet 3. As for the leak-proof sheet 8, the surface sheet 2, the absorption sheet 4, and the back sheet 3 are smaller than the leak-proof sheet 8, and are not included in the pressing part 7.
In the present specification, the “absorbent article having water decomposability” may be simply referred to as an absorbent article.

In the absorbent article 1 shown in FIGS. 1 and 2, the top sheet 2 is integrated by being bonded to the absorbent sheet 4, and the integrated top sheet and the absorbent sheet 5 have a plurality of circular shapes. It has an opening 6. As shown in FIG. 2, the integrated top sheet and absorbent sheet 5 are bonded to the leak-proof sheet 8 via the bonding portion 9, and the leak-proof sheet 8 is bonded to the back sheet 3. It is bonded via the part 9.
In FIG. 2, an adhesive portion for integrating the top sheet 2 and the absorbent sheet 4 is omitted.

Further, in the absorbent article shown in FIGS. 1 and 2, the top sheet 2 is formed from a spunlace nonwoven fabric, and the absorbent sheet 4 is formed from an airlaid nonwoven fabric containing a water-soluble binder.

In the absorbent article shown in FIGS. 1 and 2, the integrated topsheet and absorbent sheet 5 have a convex portion 10 and a plurality of concave portions 11, and the first opening 6 is formed in the concave portion 11. Has been. As shown in FIG. 2, by forming the first opening in the concave portion of the integrated topsheet and absorbent sheet, the fracture surface of the spunlace nonwoven fiber at the edge of the first opening can be changed by the user. This makes it difficult for the user to feel irritation during wearing.

In the absorbent article shown in FIG. 1 and FIG. 2, since there are a plurality of concave portions in the convex portion covering almost the entire area of the topsheet, there is only one convex portion. In another embodiment of the article, for example, a plurality of convex portions may exist in one concave portion that covers substantially the entire area of the topsheet.

As shown in FIG. 2, by providing a concave and convex shape on the integrated topsheet and absorbent sheet, it is possible to reduce the contact area between the user's skin and the skin contact surface of the absorbent article. The sticky feeling of time can be reduced.

FIG. 3 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure, and is a cross-sectional view corresponding to the XX cross section of the region X ′ of FIG. The view of the absorbent article 1 shown in FIG. 3 viewed from the top sheet side is almost the same as FIG. 1 except that the diameter of the opening looks slightly smaller. The absorbent article 1 shown in FIG. 3 includes a top sheet 2, a back sheet 3, and an absorbent sheet 4 between the top sheet 2 and the back sheet 3, and between the absorbent sheet 4 and the back sheet 3. Further, a leak-proof sheet 8 is included.

In the absorbent article 1 shown in FIG. 3, the surface sheet 2 is integrated by being bonded to the absorption sheet 4, and the integrated surface sheet and the absorption sheet 5 include a plurality of first openings 6. Have In the absorbent article 1 shown in FIG. 4, the absorbent sheet 4 is also bonded to the leak-proof sheet 8 via the adhesive part 9, and the leak-proof sheet 8 is attached to the back sheet 3 with the adhesive part 9. Is glued through. In FIG. 3, an adhesive portion for integrating the top sheet 2 and the absorbent sheet 4 is omitted. Further, in the absorbent article 1 shown in FIG. 3, the first opening 6 is formed in the recess 11 in the same manner as the embodiment shown in FIG. 2, but the first opening 6 is in the recess. 11 differs from the embodiment shown in FIG. 2 in that it exists in a part of the bottom rather than the entire bottom of 11.

The shape of the concave part, the convex part, and the first opening as shown in FIGS. 2 and 3 is, for example, a surface sheet and an absorbent sheet integrated between a punching die having a pair of projecting parts and a hollow part. Can be formed by punching out a part of the integrated surface sheet and absorbent sheet. By appropriately setting the shape of the protruding portion, for example, by using a sharp protruding portion at the tip, it is possible to form a concave portion, a convex portion and a first opening as shown in FIG. Then, for example, the first opening can be formed while slightly compressing the periphery by using a projecting portion that is not so sharp and thickens as it approaches the root.

The absorbent article of the present disclosure has the first opening as shown in FIG. 2 and FIG. 3, so that after the waste is flushed into the flush toilet, water can quickly enter from the first opening, and the absorbent sheet can be put in early. It can be hydrolyzed and then the entire absorbent article can be hydrolyzed early. Moreover, at the time of use of an absorbent article, the discharged body fluid can be quickly taken into the absorbent article through the first opening.

In the embodiment of the absorbent article shown in FIGS. 2 and 3, the integrated topsheet and absorbent sheet have a convex portion and a plurality of concave portions, and the first opening is formed in the concave portion. However, in the absorbent article of the present disclosure, the first opening may not be formed in the recess.

FIG. 4 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure, and is a cross-sectional view corresponding to the XX cross section of the region X ′ of FIG. The figure which looked at the absorbent article 1 shown by FIG. 4 from the surface sheet side is as substantially the same as FIG. The absorbent article 1 shown in FIG. 4 includes a top sheet 2, a back sheet 3, and an absorbent sheet 4 between the top sheet 2 and the back sheet 3, and between the absorbent sheet 4 and the back sheet 3. Further, a leak-proof sheet 8 is included.

In the absorbent article 1 shown in FIG. 4, the surface sheet 2 is integrated by being bonded to the absorption sheet 4, and the integrated surface sheet and the absorption sheet 5 include a plurality of first openings 6. Have In the absorbent article 1 shown in FIG. 4, the absorbent sheet 4 is also bonded to the leak-proof sheet 8 via the adhesive part 9, and the leak-proof sheet 8 is attached to the back sheet 3 with the adhesive part 9. Is glued through. In FIG. 4, an adhesive portion for integrating the top sheet 2 and the absorbent sheet 4 is omitted.

As in the embodiment of the absorbent article shown in FIG. 2 and FIG. 3, the absorbent article 1 shown in FIG. It can be hydrolyzed early and then the entire absorbent article can be hydrolyzed early. Moreover, at the time of use of an absorbent article, the discharged body fluid can be quickly taken into the absorbent article through the first opening.

In the embodiment of the absorbent article shown in FIGS. 2 to 4, a leakproof sheet is included between the absorbent sheet and the back sheet, but the absorbent article of the present disclosure is shown in FIG. 5, for example. Thus, it is not necessary to include a leak-proof sheet.

FIG. 5 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure, and is a cross-sectional view corresponding to the XX cross section of the region X ′ of FIG. The figure which looked at the absorbent article 1 shown by FIG. 5 from the surface sheet side is substantially the same as FIG. The absorbent article 1 shown in FIG. 5 includes a top sheet 2, a back sheet 3, and an absorbent sheet 4 between the top sheet 2 and the back sheet 3, but between the absorbent sheet 4 and the back sheet 3. There is no leak-proof sheet. In FIG. 5, an adhesive portion for integrating the top sheet 2 and the absorbent sheet 4 is omitted. In the absorbent article 1 shown in FIG. 5, the top sheet 2 is integrated by being bonded to the absorbent sheet 4, and the absorbent sheet 4 is bonded to the back sheet 3 through the bonding portion 9. Yes.

As in the embodiment of the absorbent article shown in FIGS. 2 to 4, the absorbent article 1 shown in FIG. 5 is allowed to quickly enter water from the first opening after being discarded in the flush toilet, It can be hydrolyzed early and then the entire absorbent article can be hydrolyzed early. Moreover, at the time of use of an absorbent article, the discharged body fluid can be quickly taken into the absorbent article through the first opening.

In the embodiment of the absorbent article shown in FIG. 1, a plurality of first openings 6 are formed on the entire surface of the integrated topsheet and absorbent sheet. However, in the absorbent article of the present disclosure, the first opening is provided. The number of parts is not particularly limited, and even if there is one first opening per absorbent article, water disintegration can be improved after disposal in the flush toilet. The number of the first openings may be the majority. For example, as shown in FIG. 1, there may be 400 or more first openings per absorbent article. However, when the number of the first openings increases, the area where the absorber does not exist increases when observed from the skin surface side. Therefore, when it is necessary to absorb a large amount of body fluid, It will be necessary to keep the number within a certain range.

Further, the area per one first opening is not particularly limited, but the extent that the user's skin is not in direct contact with the integrated surface sheet and the leak-proof sheet under the absorbent sheet, or the absorbent article When it does not include a leak-proof sheet, it preferably has an area that does not directly contact the back sheet. Moreover, it is preferable that a 1st opening part has a magnitude | size which is hard to clog after absorbing a bodily fluid. From the above viewpoint, the first opening preferably has an area of about 0.1 to about 5.0 mm ² per first opening, and has an area of about 0.3 to about 3.0 mm ² . More preferably, it has an area of about 0.7 to about 2.0 mm ² .
In the present specification, the “area of the first opening” means the projected area of the first opening when the absorbent article is observed from the surface sheet side.

Furthermore, in the absorbent article of the present disclosure, the area ratio of the first opening is preferably about 5 to about 40%, and more preferably about 10 to about 30%. When the area ratio is less than about 5%, water disintegration may not be improved. When the area ratio is more than about 40%, the strength of the surface sheet may be reduced and may be fluffed during use.

In addition, in this specification, "the area ratio of a 1st opening part" means the ratio with respect to the total area of the surface sheet of an absorbent article of the sum total of the area of a 1st opening part. Further, in this specification, “the total area of the surface sheet” means the projected area of the surface sheet when the absorbent article is observed from the surface sheet side, as in the case of the first opening.

In the absorbent article shown in FIG. 1, the first openings are uniformly arranged over the integrated topsheet and absorbent sheet, but in the absorbent article of the present disclosure, the number of first openings is In addition, there may be a distribution in the area ratio or the like, for example, embodiments as shown in FIGS.

FIG. 6 is a view of another embodiment of the absorbent article of the present disclosure as viewed from the surface sheet side. The absorbent article 1 shown in FIG. 6 is a panty liner having water disintegration, and includes a top sheet 2, an absorbent sheet 4, a leak-proof sheet 8, and a back sheet 3 in that order, and its peripheral edge. The squeezed part 7 formed by squeezing the top sheet 2, the absorbent sheet 4 and the back sheet 3 is provided in the part. The leak-proof sheet 8 is smaller in size than the top sheet 2, the absorbent sheet 4, and the back sheet 3, and is not included in the squeezed portion 7.

In the absorbent article 1 shown in FIG. 6, the surface sheet 2 is integrated by being bonded to the absorption sheet 4, and the integrated surface sheet and the absorption sheet 5 include a plurality of first openings 6. Have In the absorbent article 1 shown in FIG. 6, the integrated topsheet and absorbent sheet 5 have the first opening 6 in a range in contact with the leak-proof sheet 8, but in a range not in contact with the leak-proof sheet 8. The first opening 6 does not exist.
As FIG. 6 shows, the rigidity of an absorbent article can be made uniform by providing a 1st opening part in the range which touches a leak-proof sheet.

In the absorbent article of the present disclosure, the area where the leak-proof sheet is present has a greater number of layers and the rigidity of the absorbent article tends to be higher than the area where the leak-proof sheet is not present. The absorbent article is easily bent along the boundary of the leak-proof sheet. Therefore, by providing the first opening only in the area in contact with the leakproof sheet, that is, the area where the leakproof sheet exists, the rigidity of the area of the absorbent article is reduced, and the area where the leakproof sheet exists, It is possible to reduce the difference in rigidity from the region where there is no leakage sheet.

FIG. 7 is a view of another embodiment of the absorbent article of the present disclosure as viewed from the top sheet side, as in FIG. 6.
In the absorbent article 1 shown in FIG. 7, the elements other than the first opening 6 are the same as those of the absorbent article shown in FIG. In the absorbent article 1 shown in FIG. 7, the first opening 6 has a substantially elliptical shape, and the major axis of the substantially elliptical first opening 6 is orthogonal to the longitudinal direction L of the absorbent article 1. Yes. By making the major axis of the first opening 6 perpendicular to the longitudinal direction L of the absorbent article, the rigidity in the longitudinal direction of the absorbent article is reduced, and the absorbent article is bent in the longitudinal direction L of the absorbent article. It becomes easy to follow the shape of the user's body.

When the absorbent article is worn, the central portion in the longitudinal direction of the absorbent article tends to be greatly subjected to inward force by being sandwiched between both feet. Therefore, the absorbent article is likely to be twisted in the width direction. Therefore, by making the rigidity in the width direction of the absorbent article higher than the rigidity in the longitudinal direction, it is possible to make it difficult for the absorbent article to be twisted. By making it difficult to generate a twist, it becomes difficult to memorize a sense of incongruity when walking.
When the rigidity in the longitudinal direction of the absorbent article is desired to be higher than the rigidity in the width direction, the first opening having a substantially elliptical shape is absorbed by the major axis of the first opening 6 having a substantially elliptical shape. What is necessary is just to arrange | position so that it may become parallel to the longitudinal direction L of the property article 1.

In addition, in this specification, the shape of a 1st opening part means the shape of a 1st opening part at the time of observing an absorbent article from the surface sheet side.
The shape of the first opening is a circle, a square, a rectangle, a triangle, etc. in addition to a case where it is circular as shown in FIGS. be able to.

FIG. 8 is a view of another embodiment of the absorbent article of the present disclosure as viewed from the top sheet side, as in FIG. 6. In the absorbent article 1 shown in FIG. 8, the elements other than the first opening 6 are the same as those of the absorbent article shown in FIG.

In the absorbent article 1 shown in FIG. 8, in the integrated surface sheet and absorbent sheet 5, the area ratio of the first openings 6 in the side edge regions S in the longitudinal direction L of the absorbent article 1 is the absorbent article. 1 is higher than the area ratio of the first opening 6 in the central region C in the longitudinal direction.

The central region of the absorbent article in the longitudinal direction is the place where body fluids are most likely to adhere, and there are many contacts with the skin. As a result, if there are a plurality of openings in the central region in the longitudinal direction of the absorbent article, the durability of the absorbent article may be reduced. Accordingly, the area ratio of the opening in the central region in the longitudinal direction of the absorbent article is lowered, the durability of the absorbent article is improved, and the area ratio of the opening in both side edge areas of the absorbent article is increased, thereby improving water decomposability. Can be improved.

Moreover, in another embodiment of the absorbent article of the present disclosure, in the integrated topsheet and absorbent sheet, the area ratio of the first opening in the central region in the longitudinal direction of the absorbent article is the length of the absorbent article. It may be higher than the area ratio of the first opening in the side edge region in the direction.

Moreover, in the absorbent article of this indication, a back surface sheet may have an opening part. When the back sheet has an opening, the water decomposability of the absorbent article of the present disclosure can be further improved.
In addition, in this specification, in order to distinguish the opening part which a back surface sheet has from the 1st opening part which the integrated surface sheet and absorption sheet have, it may be called a "2nd opening part."

FIG. 9 is a cross-sectional view of another embodiment of the absorbent article of the present disclosure, and corresponds to the XX cross section of FIG. The absorbent article 1 shown in FIG. 9 is a panty liner having water decomposability, and includes a top sheet 2, an absorbent sheet 4, a leak-proof sheet 8, a back sheet 3, and an adhesive portion 13 in that order. And has a squeezed portion 7 formed by squeezing the top sheet 2, the absorbent sheet 4 and the back sheet 3 at the peripheral edge thereof. The leak-proof sheet 8 is smaller in size than the top sheet 2, the absorbent sheet 4, and the back sheet 3, and is not included in the squeezed portion 7. Further, in the absorbent article 1 shown in FIG. 8, the integrated topsheet and absorbent sheet 5 have a convex portion 10 and a plurality of concave portions 11, and the first opening 6 is formed in the concave portion 11. Has been.

In the absorbent article 1 shown in FIG. 9, the back sheet 3 has a plurality of second openings 12 in a region not in contact with the adhesive portion 13.
The area and shape per second opening are generally the same as those of the first opening. That is, the first opening preferably has an area of about 0.1 to about 5.0 mm ² per first opening, and preferably has an area of about 0.3 to about 3.0 mm ^2. More preferably, it has an area of about 0.5 to about 2.0 mm ² .

The second opening may have a shape such as a circle, a substantially oval shape, a rhombic shape, a square, a rectangle, or a triangle.
In the present specification, the “area of the second opening” means the projected area of the second opening when the absorbent article is observed from the back sheet side.

The second opening is preferably present in a region not in contact with the adhesive portion. The adhesive part generally has a slow speed of dissolving or dissolving in water, and when the second opening is in a region in contact with the adhesive part, the adhesive part covers the second opening and is discarded in the flush toilet This is because the entry of water at the time may be hindered.

In addition, when the absorbent article does not include a leak-proof sheet, the second opening is located away from the central part in contact with the body fluid excretion part, for example, the peripheral part, the longitudinal side edge part, the longitudinal part of the absorbent article It is preferable that it exists in a direction edge part etc. This is because the absorbed body fluid may pass through the absorbent article and move to the user's underwear.
When the absorbent article includes a leak-proof sheet, the second opening can be present in a region in contact with the leak-proof sheet and / or a region not in contact with the leak-proof sheet.

The absorbent article shown in FIG. 1 and FIGS. 6 to 8 has a squeezed portion formed by squeezing the outer portion of the topsheet, absorbent sheet, and backsheet from the leakproof sheet, In the absorbent article of this indication, the above-mentioned pressing part does not need to be.

In addition, there exists an advantage which can raise the joint strength at the time of use of a surface sheet, an absorption sheet, and a back surface sheet by providing a pressing part. Moreover, there exists an advantage which the water disintegration at the time of discarding to a flush toilet improves by squeezing parts other than a leak-proof sheet. Moreover, in order to improve the water disintegration property when discarded in the flush toilet, it is preferable that the absorbent sheet is present at the end in the planar direction of the absorbent article. When the absorbent sheet is present at the end in the planar direction of the absorbent article, when it is discarded in the flush toilet, the absorbent sheet quickly disintegrates first, promoting water disintegration from the inside of the absorbent article and absorbing This is because the functional article can be separated into a front sheet, a back sheet and the like.

In the absorbent article of the present disclosure, the top sheet is formed from a spunlace nonwoven fabric. Since the surface sheet is in direct contact with the user's skin, high strength is required to prevent fluffing, breakage, and the like due to friction during use. On the other hand, in view of water disintegration, it is preferable that the fiber is a short fiber and does not have a heat-sealed portion. When these are comprehensively judged, a spunlace nonwoven fabric is considered suitable as the surface sheet.

However, when the unevenness is provided on the top sheet, a certain bulkiness is required, but the spunlace nonwoven fabric has a high basis weight by making it bulky. As the basis weight increases, the spunlace nonwoven fabric becomes stiff, the texture is reduced, and the water disintegration is reduced.
Therefore, by reducing the thickness of the spunlace nonwoven fabric as the surface sheet and adhering and integrating the bulky and excellent water disintegration absorbent sheet, the durability, water disintegration, and shape of the surface sheet are integrated. The degree of freedom is considered to improve.

In consideration of water disintegrability, the spunlace nonwoven fabric as the top sheet preferably has a fiber length of about 20 to about 70 mm. When the fiber length is less than about 20 mm, when forming a spunlace nonwoven fabric, the fibers are not easily entangled with each other, the strength of the formed nonwoven fabric may be insufficient, and the fiber length exceeds about 60 mm. , Water disintegration tends to decrease,

In the absorbent article of the present disclosure, the absorbent sheet is formed from an airlaid nonwoven fabric containing a water-soluble binder. In consideration of water decomposability, the absorbent sheet is preferably a single fiber, does not have a thermal attachment part, and is preferably bulky in consideration of the degree of freedom of shape. From these viewpoints, in the absorbent article of the present disclosure, an airlaid nonwoven fabric containing a water-soluble binder was selected as the absorbent sheet.

When the fiber length of the absorbent sheet is discarded in a flush toilet or the like, in order to improve the peelability between the absorbent sheet and the backsheet, or the peelability between the absorbent sheet and the leakproof sheet, It is preferably shorter than the fiber length of the top sheet. Specifically, the absorbent sheet preferably has a fiber length of about 0.5 to about 7 mm. When the fiber length is less than about 0.5 mm, the fiber may pass through the gap between the fibers of the top sheet and / or the back sheet, and drop off. When the fiber length exceeds about 7 mm, an airlaid nonwoven fabric is produced. However, unevenness tends to occur.

The integrated surface sheet and absorbent sheet preferably have a thickness of about 1.4 mm to 2.0 mm, and also when a weight corresponding to 50 g / cm ² assuming body pressure is applied, It preferably has a thickness of 1 mm or more.

In the present specification, the “water-soluble binder” includes not only a binder that can be dissolved in water but also a binder that can be dispersed in water.
Examples of the water-soluble binder include polyvinyl alcohol and ethylene vinyl acetate copolymer.

In the absorbent article of the present disclosure, examples of the back sheet include water-disintegrating paper containing water-dispersible fibers and water-disintegrating nonwoven fabric. Specifically, (1) pulp is used as raw material and hydrolytic paper is made into a sheet by hydrogen bonding between pulp fibers, and (2) water-dispersible fiber such as pulp and rayon is used as a raw material, and it is made into a sheet with a water-soluble binder. Water disintegrated paper, (3) water disintegrated paper formed by entanglement of water dispersible fibers, (4) water disintegratable nonwoven fabric formed by entanglement of single fiber water dispersible fibers by water jet treatment, and the like. It is done.
The back sheet may be a laminate of water-disintegrating paper, water-disintegrating non-woven fabric and the like containing the water-dispersible fiber and polylactic acid, polyvinyl alcohol and the like.
Specific examples of the back sheet include spunlace nonwoven fabric having water decomposability.

In the absorbent article of the present disclosure, the leak-proof sheet as desired can be used without particular limitation as the water-disintegrable leak-proof sheet in the art, for example, similar to the above-described back sheet. And a laminate of water-decomposable nonwoven fabric, water-degradable paper and the like, and water-decomposable paper, water-degradable nonwoven fabric and the like, and polylactic acid, polyvinyl alcohol and the like. Examples of the leak-proof sheet include films of polylactic acid and polyvinyl alcohol.
Specific examples of the leak-proof sheet include a laminate of a spunlace nonwoven fabric having water decomposability and polylactic acid.

In the absorbent article of the present disclosure, as an adhesive that is a raw material of an adhesive part that adheres a top sheet, an absorbent sheet, a back sheet, and an optional leak-proof sheet, it is usually used in the technical field of water-decomposable absorbent articles. Water-soluble adhesives such as emulsions of polyvinyl alcohol.

Further, as the adhesive, a water-insoluble adhesive, for example, a styrene / butadiene based synthetic resin, which is usually used in the technical field of non-water-degradable absorbent articles, can also be used. By adopting a water-insoluble adhesive, it is particularly excellent in shape retention after absorbing liquid and durability can be improved.

As described above, since the absorbent sheet is formed of an airlaid nonwoven fabric containing a water-soluble binder and having a short fiber length, the absorbent sheet itself is excellent in water decomposability. Therefore, when it is discarded in a flush toilet, etc., the absorbent sheet is quickly hydrolyzed, that is, separated into individual fiber units, so whether the adhesive is water-soluble or water-insoluble. Separate from the sheet. Therefore, in the water-decomposable absorbent article of the present disclosure, not only a water-soluble adhesive but also a water-insoluble adhesive can be used for bonding each sheet.

In the case of using a water-insoluble adhesive for bonding each sheet, in order to increase the water disintegration property of the absorbent article of the present disclosure, the basis weight of contact coating is about 7 g / m ² or less. It is preferable to form a stripe with a width of 1 mm and to coat with a wire diameter of about 10 to about 50 μm so that the basis weight is about 3 to about 7 g / m ² in non-contact coating.
In addition, in the accompanying drawings, for example, the adhesive portion is described as being regularly arranged at a predetermined interval between the leak-proof sheet and the back sheet. In the adhesive article, it is sufficient that the bonding portion has a sufficient amount for fixing them between the two sheets to be bonded.

In the absorbent article of the present disclosure, as an adhesive that forms an adhesive part for fixing the absorbent article to the user's underwear, an adhesive usually used in the art, for example, a hot melt adhesive, for example, , Polyolefin (eg, polyethylene and polypropylene) hot melt adhesives, ethylene / vinyl acetate copolymer hot melt adhesives, synthetic rubber (eg, styrene copolymers, butadiene copolymers, isoprene copolymers) hot melt adhesives, An acrylic resin adhesive, a polyvinyl alcohol adhesive, etc. are mentioned.
The pressure-sensitive adhesive may be an acrylic emulsion having a hydrophilic protective colloid layer.

The absorbent article of this indication can be manufactured as follows, for example.
The top sheet and the absorbent sheet are integrated with an adhesive interposed therebetween, and a predetermined first opening is formed in the integrated top sheet and absorbent sheet. For example, as described above, the first opening portion has the integrated topsheet and absorbent sheet between the punching dies having a pair of projections and depressions, and the topsheet faces the projections. Then, it can be formed by punching out part of the integrated topsheet and absorbent sheet.

Next, an adhesive sheet is sandwiched between the integrated topsheet and absorbent sheet having openings, and an optional leak-proof sheet is laminated, and then an adhesive is sandwiched between the second openings as desired. A back sheet having a portion is laminated. Next, the absorbent article of the present disclosure can be manufactured by cutting the laminate into the shape of the absorbent article and, if desired, squeezing the periphery.

The absorbent article of the present disclosure can be a water-decomposable article, for example, a water-degradable panty liner, a sanitary napkin, a urine removing pad, or the like.

Hereinafter, although an example is given and this indication is explained, this indication is not limited to these examples.
[Production Example 1]
A spunlace nonwoven fabric (basis weight: 35 g / m ² , thickness: 0.157 mm, density: 0.22 g / cm ³ ) containing 80% by mass of rayon (1.1 dt × 7 mm) was prepared as a top sheet. Further, as an absorbent sheet, an airlaid nonwoven fabric (basis weight: 70 g / m ² , thickness: 1.77 mm, density) containing 90% by mass of pulp and 10% by mass of a spray binder (copolymer of ethylene and vinyl acetate). 0.04 g / cm ³ ) was prepared.
A hot melt adhesive is applied to the airlaid nonwoven fabric so as to have a basis weight of about 5 g / m ^2, and the spunlace nonwoven fabric and the airlaid nonwoven fabric are integrated to form an integrated surface sheet, Absorption sheet a was formed.

Between the punching die having a pair of protrusions and depressions, the integrated surface sheet and absorbent sheet a are arranged so that the surface sheet faces the protrusions, and then the integrated surface The laminated sheet 1 was formed by punching a part of the sheet and the absorbent sheet a to form openings on the entire surface sheet and absorbent sheet a. In the laminated sheet 1, openings having a diameter of about 1.5 mm are arranged in a 60 ° zigzag pattern, and the distance between the centers of adjacent openings is about 3.5 mm, and the opening ratio is 16. 7%.

[Production Example 2]
An opening was formed in the spunlace nonwoven fabric used as the top sheet used in Production Example 1, using the punching die used in Production Example 1. Next, a hot-melt adhesive was applied to the spunlace nonwoven fabric having an opening and the air-laid nonwoven used as the absorbent sheet used in Production Example 1 so that the basis weight was about 5 g / m ^2. The spunlace nonwoven fabric having the above and the airlaid nonwoven fabric were integrated by bonding to form a laminated sheet 2.

[Production Example 3]
The integrated topsheet and absorbent sheet a in Production Example 1 were used as the laminated sheet 3.

[Example 1 Evaluation of water disintegration]

Laminate sheets

1 and 3 are cut into a size of 70 mm × 70 mm, 400 mL of water and one of the laminate sheets 1 to 3 are put into a 500 mL beaker, and stirred at 700 rpm using a magnetic stirrer. Then, “absorption sheet water disintegration time” when the absorbent sheet finished water dissolution and “surface sheet water disintegration time” when the top sheet finished water dissolution were measured. The results are shown in Table 1 below.

From Table 1, the laminated sheet 1 in which the opening portion is provided in the top sheet and the absorbent sheet is superior in both the water-disintegrating property of the absorbent sheet and the water-disintegrating property of the top sheet as compared with the laminated sheet 3 having no opening portion. I understand that. This is because the absorbent sheet not only disintegrated from the surface exposed to the water flow on the surface opposite to the surface sheet, but also rapidly disintegrates from the surface on the surface sheet side due to water entering from the opening. Next, it is considered that the top sheet that had been made into a single layer by hydrolyzing the absorbent sheet was swallowed by a water flow and rapidly hydrolyzed.

[Example 2 Evaluation of durability]
The durability of the laminated sheets 1 to 3 on the surface sheet side was evaluated. The test method is as follows.
Laminated sheets 1 to 3 were cut into a width of 25 mm and a length of 200 mm, and set on a sample table of a tester industry AB-301 COLOR FASTNESS RUBING TESTER so that the topsheet faced up. Artificial leather was selected as the friction element, and the durability of the topsheet was evaluated under the conditions of contact area: about 1 cm ² (1 cm × 1 cm), load: 200 g, reciprocation distance: 120 mm, speed: about 30 times / minute. . The number of reciprocations at which the surface sheet broke is shown in Table 2 below as the number of reciprocations.

Table 2 shows that durability is increased by integrating the topsheet and the absorbent sheet and providing an opening. The reason why the laminated sheet 1 is more durable than the laminated sheet 2 is considered that the top sheet is integrated with the absorbent sheet. The laminated sheet 1 is more durable than the laminated sheet 3 because the laminated sheet 1 has a hollow convex portion as shown in FIG. This is thought to be because the generated frictional force could be dissipated.

Specifically, the present disclosure relates to the following aspects.
[Aspect 1]
An absorbent article having water decomposability, comprising a top sheet, a back sheet, and an absorbent sheet between the top sheet and the back sheet,
The top sheet is formed from a spunlace nonwoven fabric, and the absorbent sheet is formed from an airlaid nonwoven fabric containing a water-soluble binder,
The top sheet is integrated by being bonded to the absorbent sheet, and the integrated top sheet and absorbent sheet have a plurality of openings.
The said absorbent article characterized by the above-mentioned.

[Aspect 2]
The absorbent article according to aspect 1, wherein the integrated topsheet and absorbent sheet have a convex portion and a plurality of concave portions, and the opening is formed in the concave portion.
[Aspect 3]
The opening is disposed between a punching die having a pair of protrusions and depressions, and the integrated surface sheet and absorbent sheet are arranged so that the surface sheet faces the protrusions, The absorptive article according to

aspect

1 or 2 formed by punching out a part of the integrated surface sheet and absorbent sheet.

[Aspect 4]
The absorbent article according to any one of aspects 1 to 3, further comprising a leak-proof sheet between the absorbent sheet and the back sheet.
[Aspect 5]
The top sheet, the absorbent sheet, and the back sheet have a larger size than the leak-proof sheet, and the absorbent article has a portion outside the leak-proof sheet of the top sheet, the absorbent sheet, and the back sheet. The absorbent article of aspect 4 which has the pressing part formed by pressing.

[Aspect 6]
The absorbent article according to

aspect

4 or 5, wherein the integrated topsheet and absorbent sheet have the opening within a range in contact with the leakproof sheet.
[Aspect 7]
The absorbent article according to any one of aspects 1 to 6, wherein the opening has a substantially elliptical shape, and a major axis thereof is orthogonal to a longitudinal direction of the absorbent article.

[Aspect 8]
In the integrated surface sheet and absorbent sheet, the area ratio of the opening in the side edge region in the longitudinal direction of the absorbent article is higher than the area ratio of the opening in the central area in the longitudinal direction of the absorbent article. The absorbent article according to any one of embodiments 1 to 5.
[Aspect 9]
In the region where the back sheet has an adhesive part for fixing the absorbent article to the user's underwear on the surface opposite to the absorbent sheet, and the back sheet is not in contact with the adhesive part. Alternatively, the absorbent article according to any one of aspects 1 to 8, which has a plurality of openings.

[Aspect 10]
The absorbent article according to any one of embodiments 1 to 9, which is a panty liner.

DESCRIPTION OF SYMBOLS 1 Absorbent article 2 Top sheet 3 Back sheet 4 Absorbent sheet 5 Integrated top sheet and absorbent sheet 6 (First) opening 7 Squeeze part 8 Leakproof sheet 9 Adhesive part 10 Convex part 11 Concave part 12 Second opening part 13 Adhesive part

Claims

An absorbent article having water decomposability, comprising a top sheet, a back sheet, and an absorbent sheet between the top sheet and the back sheet,
The surface sheet is formed from a spunlace nonwoven fabric, and the absorbent sheet is formed from an airlaid nonwoven fabric containing a water-soluble binder,
The top sheet is integrated by being bonded to the absorbent sheet, and the integrated top sheet and absorbent sheet have a plurality of openings.
The said absorbent article characterized by the above-mentioned.
The absorbent article according to claim 1, wherein the integrated topsheet and absorbent sheet have a convex portion and a plurality of concave portions, and the opening is formed in the concave portion.
The opening is disposed between a punching die having a pair of protrusions and depressions, and the integrated surface sheet and absorbent sheet are arranged so that the surface sheet faces the protrusions, The absorbent article according to claim 1 or 2, wherein the absorbent article is formed by punching out part of the integrated topsheet and absorbent sheet.
The absorbent article according to any one of claims 1 to 3, further comprising a leak-proof sheet between the absorbent sheet and the back sheet.
The top sheet, the absorbent sheet, and the back sheet have a larger size than the leakproof sheet, and the absorbent article is a portion of the top sheet, absorbent sheet, and back sheet that is outside the leakproof sheet. The absorptive article according to claim 4 which has a pressing part formed by pressing.
The absorbent article according to claim 4 or 5, wherein the integrated topsheet and absorbent sheet have the opening in a range in contact with the leakproof sheet.
The absorbent article according to any one of claims 1 to 6, wherein the opening has a substantially elliptical shape, and a long axis thereof is orthogonal to a longitudinal direction of the absorbent article.
In the integrated topsheet and absorbent sheet, the area ratio of the opening in the side edge region in the longitudinal direction of the absorbent article is higher than the area ratio of the opening in the central region in the longitudinal direction of the absorbent article. The absorbent article according to any one of claims 1 to 5.
In the area where the back sheet has an adhesive part for fixing the absorbent article to the user's underwear on the surface opposite to the absorbent sheet, and the back sheet is not in contact with the adhesive part. Alternatively, the absorbent article according to any one of claims 1 to 8, which has a plurality of openings.
The absorbent article according to any one of claims 1 to 9, which is a panty liner.